Pastry Cream (Crème Pâtissière)

Before you start

Pastry cream is milk thickened with egg yolks and starch, then enriched with a little butter. It is the classic filling for fruit tarts, éclairs, cream puffs and Boston cream pie, and the base of other creams: fold in whipped cream for a lighter crème légère, or beat it into buttercream for crème mousseline. Unlike a stirred custard such as crème anglaise, the starch lets it boil, so it can set firm enough to pipe and slice.

That boil is the step most people skip. Egg yolks contain an enzyme that breaks down starch, and if it survives, a pastry cream that looked thick in the pan turns soupy overnight. Once the mixture thickens, keep whisking over the heat for a full minute of steady bubbling. Then chill it quickly with plastic pressed onto the surface, and whisk it smooth again before using.

Ingredients

• 500 ml (2 cups) whole milk
• ½ vanilla bean — or 2 tsp vanilla extract, added at the end
• 100 g (½ cup) granulated sugar — divided
• 5 large (about 90 g) egg yolks
• 40 g (⅓ cup) cornstarch
• ⅛ tsp fine salt
• 30 g (2 tbsp) unsalted butter — cold, cut into pieces

Method

1. Split the vanilla bean and scrape the seeds into the saucepan. Add the pod, the milk and half the sugar. Heat over medium until steaming with small bubbles at the edge, then turn off the heat.
2. Meanwhile, whisk the yolks with the remaining sugar, the cornstarch and the salt in a bowl until smooth, pale and thick, about 1 minute. The sugar coating the starch helps prevent lumps.
3. Remove the vanilla pod. Pour about one third of the hot milk into the yolks in a thin stream while whisking constantly, then whisk the warmed yolk mixture back into the pan.
4. Return the pan to medium heat and whisk constantly, reaching into the corners. After 2 to 4 minutes the cream will suddenly thicken and may look lumpy; keep whisking and it will smooth out.
5. When the first large bubbles break the surface, keep it bubbling and whisking for a full 60 seconds. This cooks out the starchy taste and destroys the yolk enzyme that would otherwise thin the cream later.
6. Take the pan off the heat and whisk in the butter, and the vanilla extract if using, until glossy. Press the cream through the sieve into the shallow dish to catch any bits of cooked egg.
7. Press plastic wrap directly onto the surface to stop a skin from forming. Cool for 15 minutes, then refrigerate for at least 2 hours, until cold and set.
8. Before using, scrape the cold cream into a bowl and whisk or beat it briefly until smooth and creamy. Do not overbeat, or it loosens.

Tips for success

• Use a heavy pan and keep the heat at medium. A thin pan scorches the milk on the bottom before the cream has thickened.
• For a firmer cream to slice in a Boston cream pie, add 5 g (1 tbsp) extra cornstarch. For a softer filling to spoon into a trifle, use 35 g.
• To lighten it for fruit tarts, fold 120 ml (½ cup) heavy cream, whipped to soft peaks, into the chilled and smoothed pastry cream.

Substitutions

Cornstarch

Use 50 g (⅓ cup plus 1 tbsp) all-purpose flour. The cream is a little less glossy and needs about 2 minutes of boiling to lose the raw flour taste.

Whole milk

Replace up to 120 ml with heavy cream for a richer filling. Low-fat milk works but tastes thinner and sets slightly softer.

Vanilla bean

Steep the milk with strips of citrus zest, a crushed cardamom pod or a spoon of espresso powder instead, then strain.

Variations

Chocolate pastry cream

Whisk 85 g finely chopped bittersweet chocolate into the hot cream along with the butter.

Coffee pastry cream

Dissolve 2 tsp instant espresso powder in the hot milk before tempering the yolks.

Troubleshooting

Pastry cream turned runny after chilling

It was not boiled long enough, so the yolk enzyme kept breaking down the starch. Next time, boil and whisk for a full minute after it thickens. Runny cream is hard to rescue.

Lumps or bits of scrambled egg

The yolks were heated too fast or the pan was not whisked into the corners. Push the hot cream through a fine sieve and keep the heat at medium next time.

Cream tastes starchy or chalky

It came off the heat as soon as it thickened. Keep it bubbling for the full minute, then strain.

Storage

Refrigerate pastry cream, covered with plastic on its surface, and use it within 3 days. Do not freeze it; it weeps and turns grainy when thawed. Filled pastries should stay refrigerated and not sit at room temperature for more than 2 hours.

Safety notes

The cream boils during cooking, well above the 71°C (160°F) recommended for egg dishes. Keep it and anything filled with it refrigerated. Contains egg and milk.