Italian Pistachio Pastry Cream | Crema al Pistacchio

Sep 29

11 min read

Crema al Pistacchio (Italian Pistachio Pastry Cream)

Crema al pistacchio is the filling Sicilian pastry shops run through everything they make, from cannoli to sponge cake to a spoon dessert served in a glass. The hard part is not the flavour. It is the colour. Get the ratio of egg to starch wrong and a cream that should read as soft green arrives at the table a tired olive instead. This version accepts that problem openly and builds the base on starch, keeping a single yolk back for roundness.

Yield: about 3 cups (750 ml), enough for 8 dessert servings or 14 filled choux. Prep: 15 minutes. Cook: 12 minutes. Chill: 3 hours. Total: about 3 hours 30 minutes. Difficulty: intermediate. Course: dessert component. Region: Sicily, with pistachio from Bronte on the slopes of Etna.

The Story

The pistachio that matters here comes from Bronte, a town on the western flank of Etna where the trees grow straight out of old lava. There is almost no soil to speak of, the terraces are too steep for machinery, and the whole harvest is still taken by hand in late August and early September. Bronte growers also work the tree on a two year cycle, stripping the flower buds one season so the following one carries a full crop, which means a real Bronte harvest happens in odd years only. The kernels are long and narrow, deep green inside a violet skin, and unusually high in oil. The DOP came in 2009 and production is tiny, which is why the price never behaves like a nut price.

Pistachio reached Sicily with Arab agriculture, and the Bronte dialect still calls it frastuca, from the Arabic word for the nut. The growing method is Arab too: the tree is grafted onto wild terebinth that seeds itself freely in the lava, so a Bronte orchard was not planted so much as converted, one wild stock at a time, over generations. That history sits underneath every Sicilian pistachio dessert, and it is the reason pistachio belongs to the island in a way almonds and hazelnuts, both grown there, never quite did.

Pastry cream is the other half of the story and it is a workshop tool rather than a regional dish. Crema pasticcera is what fills Italian pastry, and every good shop keeps a version of it turning over daily. Sicilian pastry chefs were folding pistachio into it long before the industry started selling pistachio paste in buckets, and that is the ingredient to be careful about now. Much of what is sold as pistachio paste is sweetened, thinned with other nuts, or coloured to a shade no pistachio ever reaches. Read the label and buy paste that lists pistachio and nothing else.

Ingredients

Quantities are for a cream that sets firm enough to pipe. For a looser cream to spoon into glasses, drop the cornstarch to 3 tablespoons (24 g) and leave everything else alone.

For the cream base

Whole milk, 2 cups (480 ml)
Granulated sugar, 1/2 cup (100 g)
Cornstarch, 1/4 cup (32 g)
Egg yolk, large, 1
Fine sea salt, 1/8 tsp (0.5 g)

For the pistachio

Pure pistachio paste, unsweetened, 100 percent Bronte if you can get it, 3 1/2 oz (100 g)
Shelled raw pistachios, unsalted, 1 oz (30 g)

For finishing

Unsalted butter, cold, cut small, 1 tbsp (14 g)
Heavy cream, 2 tbsp (30 ml)
Pure vanilla extract, 1/2 tsp (2.5 ml), optional

The paste does the work and the raw kernels are there for the top, chopped at the last moment so they keep their crack. Use whole milk: skimmed milk gives a thinner cream and a duller colour, because fat carries the pistachio flavour and lifts the green.

Preparation

Dispersing the pistachio paste in cold milk

Put the pistachio paste in a bowl with about 1/2 cup (120 ml) of the cold milk and work it with a small whisk until it is completely loose and uniform, with no grit of paste left on the side of the bowl. Pure pistachio paste is stiff and slightly oily straight from the jar, and cold milk breaks it down more patiently than hot liquid does. Pour this into the rest of the milk in a heavy saucepan and whisk it smooth. The milk should look pale green and slightly cloudy, with no visible specks.

Whisking the starch into the yolk and sugar

In a separate bowl whisk the sugar, cornstarch and salt together while they are dry, so the starch is coated in sugar crystals and cannot clump later. Add the single yolk and whisk to a thick sandy paste, then loosen it with three or four tablespoons of the green milk until it pours. One yolk is not much to work with, so take the time to get this mixture genuinely smooth: any lump surviving here will be a lump in the finished cream.

Bringing the pistachio milk up to temperature

Set the saucepan over medium heat and bring the pistachio milk to a bare simmer, stirring across the whole base with a flat whisk or a silicone spatula. Pistachio solids are heavy and they settle, and anything sitting on the bottom of the pan will scorch and turn the cream bitter well before you can smell it. Do not walk away and do not let the milk reach a rolling boil at this stage.

Cooking the cream to the boil and holding it

Pour a third of the hot milk into the yolk and starch mixture, whisking, then return everything to the pan. Raise the heat slightly and keep stirring. The cream will thicken suddenly at around 185°F (85°C) and then, thirty seconds later, come to a slow thick boil that lifts and falls. Hold it there for a full minute, still stirring. Starch creams need that minute: cut it short and the cream both tastes of raw starch and thins out overnight, because the enzyme in the yolk has not been destroyed.

Finishing with butter, cream and vanilla

Take the pan off the heat and stir in the butter, the heavy cream and the vanilla if you are using it. Stir only until the butter disappears. The cream should be glossy, thick and clearly green. Taste it now, while you can still correct it: it wants to be sweet but not sugary, with the pistachio arriving late rather than immediately. If it tastes flat, a pinch more salt is the right correction.

Cooling flat and fast

Scrape the cream into a shallow tray in a layer no thicker than 1 inch (2.5 cm) and press plastic film directly onto the surface, with no air between film and cream. A deep bowl holds heat for an hour and leaves you a cream that has cooked on in its own warmth and set dense. Flat and covered, it comes down to room temperature in about 20 minutes. Refrigerate at least 3 hours. It will be firm and slightly rubbery straight from the fridge, which is normal. Whisk it hard for fifteen seconds, or give it ten seconds in a food processor, and it comes back glossy and pipeable.

Plating

As a dessert in its own right, pipe the cream into a small straight sided glass and stop well short of the rim, so there is room for something dry on top. Chopped raw pistachio is the honest answer, cut coarse with a knife and scattered only as the glass goes out. A shard of thin crisp pastry leaning against the side gives the spoon something to break through.

As a filling, pipe it cold and pipe it firm. Warm cream slumps inside a cannolo and soaks the shell within minutes. Keep the finished pastry unfilled until service, then fill from both ends with a plain 1/2 inch (12 mm) tip and wipe the openings clean. Serve at refrigerator temperature or slightly above, never cold from the back of the fridge, where the pistachio flavour closes up completely.

Professional Technique

The technique that defines this recipe is a subtraction, and it is the one thing separating a green pistachio cream from a khaki one. A classical crema pasticcera is built on four to six yolks per 2 cups of milk, and those yolks are what make it yellow. Yellow is not a neutral background. Put a green pistachio paste into a yellow custard and the two colours do not sit side by side, they mix, and what comes out is the dull olive tone you see in most pistachio fillings on a counter. No amount of better paste fixes it, because the yellow is doing exactly what yellow does.

So the yolks come out and the starch takes over the job of setting the cream. One yolk in this quantity of milk is enough to give the fat, the lecithin and the faint savoury depth that make a cream taste like pastry cream rather than like sweetened cornstarch, while contributing almost no colour. The cornstarch goes up to 1/4 cup (32 g) to carry the structure the missing yolks were providing. What arrives is a cream that reads green because the pistachio is the only pigment in the bowl.

The cost is real and worth stating plainly. Egg set custard is silky, because coagulated protein holds water in a soft loose network that collapses smoothly under the tongue. Starch set custard is more compact and slightly more elastic, cleaner on the palate but less voluptuous, and it cuts with a defined edge instead of flowing. That is a trade, not a fault, and which side you want depends on the job. For piping into pastry, or anything that has to hold a shape, the starch heavy version is better. For a cream eaten off a spoon, where texture is the whole pleasure, put two yolks in and accept a duller green.

Texture and Moisture Control

Cornstarch sets by gelatinizing: the granules swell in hot liquid, burst and release long chains that trap water. That process needs real heat and a little time, which is why the cream has to reach a proper boil and stay there a full minute. Underheated starch thickens on the stove and then gives the water back in the refrigerator, and you find a puddle under the cream the next morning. Over stirred starch does the opposite: the chains shear apart and the cream goes loose no matter how long it chills.

Moisture control after cooking is mostly about the surface and the depth. Film pressed onto the cream stops the skin that forms when water evaporates from the top and leaves a rubbery lid you can never whisk back in. A shallow layer matters just as much, because a cream cooling slowly in a deep bowl keeps working and sets tighter than intended. Once cold, the set is firm and a little stiff, and it is meant to be. The final whisk is not a repair, it is a step: it breaks the starch network down to a smooth glossy state that stays put for a day.

Professional Mise en Place

Everything in this recipe is done ahead except the whisking and the chopped nuts, which is why it suits service so well.

Equipment and tools

Heavy bottomed saucepan, 2 quart, and a flat whisk that reaches the corners
Shallow tray or hotel pan for cooling, plus plastic film
Digital thermometer, useful rather than essential
Piping bag with a plain 1/2 inch (12 mm) tip

Prepared ahead

Cream cooked, cooled flat and refrigerated, up to 3 days
Pistachio paste loosened in cold milk, up to 1 day ahead, kept covered and cold
Sugar, cornstarch and salt weighed and whisked together dry

Service setup

Cream whisked smooth and bagged no more than 2 hours before service, kept refrigerated
Raw pistachios chopped at the last moment, held dry and away from steam
Glasses or shells cold and dry, filled to order and never in advance

Chef Tips

Buy the paste before you plan the dessert. Pure pistachio paste is expensive and hard to find outside Italy, and the sweetened, coloured and nut blended versions behave differently in every respect: they are looser, sweeter and greener than the real thing. If the only paste you can get is sweetened, cut the sugar in the recipe by a third and taste as you go.

Weigh the cornstarch rather than measuring it by volume. A cup of cornstarch packs to wildly different weights depending on how it was scooped, and this cream lives or dies by that number. 32 g gives a firm pipeable cream, 24 g a loose spoonable one, and the difference between them is about half a tablespoon.

Keep the whisk moving across the base of the pan, not around the sides. Pistachio solids sink and the scorching happens in the middle of the pan where you cannot see it. One patch of caught paste puts a bitter note through the whole batch, and there is no correction for it.

If the cream comes out of the fridge with lumps, push it through a fine mesh sieve after whisking rather than whisking harder. Extra beating shears the starch and thins the cream, while the sieve costs a minute and leaves the set intact.

Common Mistakes

Using a full yolk custard as the base. Four or five yolks give a yellow cream, and yellow plus green is olive. If the colour matters to you, the yolks have to come down and the starch has to come up. This is the single reason most pistachio pastry cream looks the way it does.

Pulling the cream off as soon as it thickens. Thickening happens before the starch is fully cooked. Take it off there and you get a raw starch taste and a cream that weeps water overnight. Let it reach a slow thick boil and keep it there for a full minute.

Cooling it in the bowl it was cooked in. A deep mass of hot cream carries on setting for the best part of an hour and finishes dense and pasty. Spread it in a shallow tray, film pressed onto the surface, and it stops cooking in twenty minutes.

Overbeating the cold cream. The set cream needs fifteen seconds of firm whisking, not two minutes. Push past that and the gelatinized starch shears, the cream loosens, and nothing brings the body back.

Chopping the pistachios early. Cut nuts lose their crack within an hour of sitting on a tray and go soft the moment they meet a moist surface. Chop them as the glasses go out and not before.

Wine Pairing

Moscato d'Asti DOCG: The lightest and most forgiving match. Its sweetness sits just below that of the cream, which keeps the dessert tasting sweet rather than the wine, and the low alcohol never heats a delicate nut flavour. The gentle sparkle matters most: a starch set cream coats the palate, and those bubbles lift it away between spoonfuls where a still wine would let it build.

Vin Santo del Chianti Classico DOC: The pairing with the most to say. Long oxidative ageing in small barrels gives dried fig, walnut and a bitter almond finish, and that nutty register runs directly alongside the pistachio instead of contrasting with it. Its acidity is high enough to cut the butter and the milk fat, and the alcohol gives the wine enough presence to stand up to a spoonable dessert.

Malvasia delle Lipari DOC: Sicilian, and closest to the geography of the dish. Grapes dried on the volcanic Aeolian islands give dried apricot, candied citrus peel and a faint saline edge that the salt in the cream picks up. It is sweet without being thick, and that restraint keeps it from flattening a flavour as quiet as pistachio.

Greco di Bianco DOC: A Calabrian passito made in tiny quantity, and the most aromatic choice here. Bergamot, orange blossom and honey give the plate an upper register it does not have on its own, while a firm acid spine cuts through fat that the more compact starch texture leaves on the tongue. Serve it at around 54°F (12°C) in a small glass.

Storage & Reheating

The cream keeps refrigerated for 3 days in a sealed container with film pressed onto the surface. It is at its best on the first two days, and by the third the pistachio has faded. Never leave it uncovered: it takes on refrigerator smells faster than almost any other pastry component.

Do not freeze it. Starch set creams separate on thawing, the water comes out of the network and no amount of whisking puts it back, and you are left with a grainy liquid. Reheating is not a thing that happens to pastry cream either. To bring it back to a usable state, whisk it cold and briefly, or give it a short blitz in a food processor, and stop the moment it is glossy. Filled pastry is different: a cannolo or a choux has a few hours, not a day.

Nutrition

Per serving, based on 8 dessert portions:

Calories: 265 kcal
Total Fat: 15 g
Saturated Fat: 4.5 g
Trans Fat: 0 g
Unsaturated Fat: 10 g
Cholesterol: 35 mg
Sodium: 60 mg
Total Carbohydrates: 26 g
Fiber: 1.5 g
Total Sugars: 18 g
Added Sugars: 12 g
Protein: 6 g
Lactose: 3 g
Principal micronutrients: vitamin B6, thiamine, copper, manganese, potassium, phosphorus, calcium