Boston Cream Pie Filling: What Cream is Used?

Boston cream pie, a beloved dessert hailing from the city of Boston, is a delightful combination of a yellow cake base, a creamy custard filling, and a chocolate glaze. But what exactly is the cream in Boston cream pie? Let's delve into the details of this iconic dessert and uncover the secret behind its creamy center.

At the heart of Boston cream pie lies a rich, velvety custard known as pastry cream or crème pâtissière. This is the cream that gives the dessert its name and distinctive character. But what ingredients make up this delectable cream?

Ingredients of Pastry Cream

The primary ingredients of pastry cream are milk, eggs, sugar, and cornstarch. These simple components come together to create a smooth, luscious custard that serves as the perfect complement to the cake and chocolate topping.

Milk provides the base for the cream, while eggs contribute to its richness and structure. Sugar sweetens the cream, while cornstarch acts as a thickener, giving the custard its characteristic creamy texture.

Milk: The Foundation of Pastry Cream

Milk is the key ingredient in pastry cream, providing the base for the custard. It can be made with whole milk, 2%, or even skim milk, depending on the desired richness. The milk is heated and then tempered into the egg yolks to prevent them from scrambling.

Some recipes also call for heavy cream to be added to the milk, which enhances the creaminess and richness of the final custard. However, this is not always necessary, and a simple milk-based pastry cream can be just as delicious.

Eggs: The Secret to Creamy Pastry Cream

Egg yolks are responsible for the creamy texture and rich flavor of pastry cream. They act as a thickener and provide the custard with its velvety smoothness. The yolks are whisked together with sugar before the tempered milk is gradually poured in, creating an emulsion that thickens as it cooks.

Using only egg yolks ensures that the pastry cream remains smooth and creamy. The whites are not needed for this particular application, as they do not contribute to the desired texture or flavor. However, some recipes may call for the addition of a small amount of egg whites for extra lightness.

The Science Behind Pastry Cream

Understanding the science behind pastry cream helps explain how these simple ingredients come together to create such a delightful dessert. The process involves a combination of cooking, thickening, and emulsification.

The heat from cooking causes the eggs and cornstarch to thicken, while the milk proteins coagulate, creating a smooth and creamy custard. The sugar also plays a role in this process, helping to stabilize the emulsion and prevent the custard from separating.

Cooking Pastry Cream

To make pastry cream, the milk is heated until it just begins to simmer. Meanwhile, the egg yolks and sugar are whisked together until pale and thick. The hot milk is then slowly poured into the egg yolk mixture, tempering the eggs and preventing them from scrambling.

The tempered egg mixture is then returned to the saucepan and cooked over medium heat, stirring constantly, until it thickens enough to coat the back of a spoon. This usually takes about 5-10 minutes. The custard is then strained and allowed to cool before being used to fill the Boston cream pie.

Stabilizing Pastry Cream

To ensure that the pastry cream remains smooth and creamy, it is important to stabilize it with sugar and a small amount of butter. The sugar helps to stabilize the emulsion, preventing the custard from separating or weeping. The butter adds richness and helps to prevent a skin from forming on the surface of the custard as it cools.

Some recipes also call for the addition of vanilla extract or vanilla bean paste to enhance the flavor of the pastry cream. This is an optional step, but it can add an extra layer of depth and complexity to the dessert.

Variations on Pastry Cream

While the classic Boston cream pie features a simple pastry cream filling, there are many variations on this dessert that incorporate different flavors and ingredients. Some popular variations include:

Vanilla Bean Pastry Cream

For an extra touch of elegance, infuse the milk with a vanilla bean pod before heating it. The vanilla bean seeds and pod are then removed before tempering the eggs. The resulting pastry cream has a beautiful vanilla speckled appearance and a rich, aromatic flavor.

To make vanilla bean pastry cream, simply split a vanilla bean pod lengthwise, scrape out the seeds, and add both the seeds and the pod to the milk as it heats. Once the custard has thickened, remove the vanilla bean pod before straining the cream.

Lemon Curd Pastry Cream

For a tangy twist on the classic Boston cream pie, try incorporating lemon curd into the pastry cream. The bright, citrusy flavor of the lemon curd complements the rich, creamy custard and adds a refreshing note to the dessert.

To make lemon curd pastry cream, simply fold in store-bought or homemade lemon curd after the custard has thickened and cooled slightly. Be sure to adjust the sugar content of the pastry cream to account for the added sweetness of the lemon curd.

In the world of pastry cream, the possibilities are endless. From classic vanilla to exotic flavors like lavender or cardamom, there's a pastry cream for every taste. So, the next time you indulge in a Boston cream pie, you'll appreciate the art and science behind that creamy, delicious center.