How to Fill Choux Pastry: Creams, Custards, and Beyond

Anyone who has ever baked choux pastry will be aware of the pleasure in that golden, crisp shell freshly baked. However, it's what is filled into the shells that really makes them irresistible. A good filling can transform a plain, ordinary pastry into something fantastic. If you are preparing éclairs, cream puffs, or profiteroles, then choosing the right filling will make all the difference.

It all depends on what your taste, occasion, and desired texture might be. Rich custards and sharp creams or, indeed savory and surprising possibilities-end. As with any pastry, filling choux demands technique; perfect crisp on the outside to complement smooth and stable on the inside.

Recipe for Choux Pastry

Ingredients

• 1 cup (240ml) water
• ½ cup (113g) unsalted butter, cubed
• 1 tsp sugar (optional, for sweet pastries)
• ¼ tsp salt
• 1 cup (125g) all-purpose flour
• 4 large eggs (room temperature)

Method:

1. Begin by heating water, butter, sugar, and salt in a saucepan over medium heat. Stir until the butter melts and the mixture starts to simmer. Reduce the heat to low and add the flour all at once. Stir thoroughly until the dough comes away from the sides of the pan and forms a ball.
2. Transfer the dough to a mixing bowl and let it cool slightly, then start adding eggs one at a time. Mix well after each addition until the dough becomes smooth, glossy, and thick but pipeable. Pipe the dough into rounds or éclairs on a prepared baking sheet and bake at 200°C for 20 minutes before reducing the heat to 180°C to finish for the last 10 minutes, checking that they cook evenly.

Alternate Fillings to try

Classic Vanilla Pastry Cream

Vanilla pastry cream is always a classic. The custard is prepared with milk, egg yolks, sugar, and cornstarch. The mixture is then cooked until it thickens, flavored with vanilla. It has a rich, smooth, and creamy texture that will contrast perfectly with the crispy choux shell. You can infuse the milk with a hint of cinnamon or citrus zest for added depth of flavor before cooking. Pastry cream can also be prepared ahead and stored in the fridge.

Whipped cream with mascarpone

The lightness of the choux pastry filling is made rich and indulgent by whipped cream and mascarpone cheese. The mascarpone will add a slightly tangy and thicker texture to the cream, so it's much more stable and can be piped easily. It can be flavored with vanilla extract, chocolate, or even a hint of liqueur like Baileys for an adult twist. This filling is lighter than the pastry cream but just as tasty, and with a perfect balance of richness and airiness.

Chocolate Ganache

For all chocolate lovers out there, it is the filling of choice and consists of an equal amount of heavy cream to dark chocolate; the ganache is melted down and mixed for a smooth glossy mixture. A little cooling of the ganache makes it thicker enough to be piped inside the choux pastry. The creamy texture of the ganache inside the light pastry provides a wonderful contrast, and you can play with different types of chocolate for varying levels of sweetness and intensity.

Lemon Curd

Lemon curd can be described as a tart alternative to custard, providing that refreshing contrast for the sweetness of choux pastry. Lemon curd is made up of lemon juice and zest, sugar, and eggs, cooked through until thick and smooth, like a very velvety butter. The sharp, bright flavor from the lemon pairs well with the richness of the pastry and can then be topped by a dust of powdered sugar if desired.

Savory Cheese Filling

Choux pastry does not have to be always sweet. A savory cheese filling can be just as wonderful. Mix softened cream cheese with sharp cheddar or goat cheese, add fresh herbs like chives or rosemary, and season to taste with salt, pepper, and a squeeze of lemon. The result is a creamy, flavorful filling perfect for elegant appetizers or as part of a brunch spread. You can even add sautéed mushrooms or caramelized onions for an extra depth of flavor.

Tips to Fill Choux Pastry

Cool Properly

Let the choux pastry shells cool completely before filling them. Hot pastry will cause the filling to melt and may result in soggy shells. The cool interior helps maintain the contrast between the light, crispy exterior and the creamy filling.

Use a Piping Bag

To smoothly and neatly fill your choux pastry, use a piping bag with a plain round tip. This way, you can conveniently fill the pastry without overstuffing or messing it up. It can also be piped with filling to ensure more uniform shapes before baking.

Pipe from the Bottom

When filling cream puffs or éclairs, pipe the filling through the bottom. This will help keep the shape of the shell intact and avoid disturbing the structure. Simply make a small hole at the base and insert the piping tip to fill the pastry.

Stabilize Whipped Cream

For whipped cream, stabilize the cream by adding a small amount of cornstarch or cream of tartar before whipping. That way, it will hold its shape inside the pastry and won't deflate too quickly.

Don't Overfill

It's tempting to fill your choux pastry with as much filling as possible, but this can make it hard to close the pastry or even break it. Fill it just enough to complement the crisp pastry without overpowering it.