The French Cake with Blueberries is a delightful dessert that combines a rich custard cake filling with a crunchy Biscoff crust and a luscious blueberry sauce. Topped with a tangy and creamy mascarpone lemon buttercream, this cake offers a harmonious blend of flavors and textures that will surely satisfy any sweet tooth.

The history of French cakes dates back centuries, with a strong tradition of exquisite pastries and desserts. French patisseries are famous for their artistry and attention to detail in creating delectable treats. Custard-based desserts, like this French Cake, are a classic in French cuisine, and the addition of blueberries adds a burst of fresh fruitiness to the dessert.

Blueberries, known for their antioxidant properties and vibrant color, are believed to have originated in North America and have been consumed by indigenous peoples for thousands of years. The fruit gained popularity in Europe and beyond in the 20th century due to its delicious flavor and health benefits.

This French Cake with Blueberries is a celebration of flavors and textures, showcasing the creativity and culinary finesse that France is renowned for.

INGREDIENTS

Custard Cake Filling:

• 2 cups (500 grams) heavy cream
• 3½ tablespoons (50 grams) butter
• 1 teaspoon vanilla extract
• ¾ cup (100 grams) all-purpose white flour
• 1¼ cups (250 grams) white granulated sugar
• 2 whole large eggs + 2 egg yolks
• ½ teaspoon salt
• Zest of one lemon
• 1¾ cups (550 grams) blueberries
• Extra butter for the mold

Biscoff Crust:

• 3 cups (750 grams) Biscoff crumbs
• 10 tablespoons (140 grams) unsalted butter, melted
• ⅔ cup (85 grams) granulated sugar

Blueberry Sauce:

• 6 cups fresh blueberries (frozen work too)
• 1½ cups (375 ml) water
• 1½ cups (300 grams) sugar
• 6 tablespoons cornstarch, mixed with 6 tablespoons cold water
• 2 tablespoons vanilla extract

Mascarpone Lemon Buttercream:

• 1 stick (113 grams) of butter, softened
• 5 oz. (140 grams) mascarpone cheese, chilled
• 2½ cups (225 grams) powdered sugar
• Zest of one lemon
• Pinch of salt

INSTRUCTIONS

Custard Cake Filling:

1. In a large bowl, whisk by hand until well combined the eggs, egg yolks, flour, sugar, lemon zest, and salt. Set aside.
2. In a small saucepan, place the heavy cream on medium heat until it starts to boil. Remove from heat and mix in the vanilla extract.
3. Slowly pour ⅓ of the hot heavy cream into the egg mixture, whisking constantly. Gradually add the remaining heavy cream in two more additions, whisking continuously. Avoid pouring all the heavy cream at once to prevent the eggs from cooking due to the high temperature.
4. Cover the bowl with plastic wrap and let the custard filling cool on the counter for 20 minutes before transferring it to the fridge for one hour.

Biscoff Crust:

1. Preheat the oven to 350°F.
2. In a food processor or blender, grind the Biscoff cookies until you get 3 cups of crumbs.
3. Mix the Biscoff crumbs with melted butter and granulated sugar in a medium bowl until well combined.
4. Press the mixture into the bottom of a 10-inch springform cake pan and slightly up the sides, ensuring it is tight and compact.
5. Pre-bake the crust for 7 minutes at 350°F before adding the custard filling. For a no-bake version, chill the crust for 2 hours before using it in the recipe.
6. Butter the edges of the springform pan, then place the blueberries on the Biscoff crust.
7. Remove the custard from the fridge and pour it into the pan. Bake the cake for 50 minutes until golden brown.
8. Remove the cake from the oven and let it cool completely on a wire rack.

Blueberry Sauce:

1. In a large saucepan over medium heat, combine the blueberries, water, and sugar. Stir frequently to avoid crushing the berries, bringing the mixture to a low boil.
2. In a small bowl, mix the cornstarch with cold water until combined. Slowly stir the cornstarch into the blueberries, taking care not to crush them.
3. Simmer until the homemade blueberry sauce thickens enough to coat the back of a metal spoon, which takes about 10 minutes.
4. Remove from heat and gently stir in the vanilla extract. Let the sauce cool completely before topping the cake.

Mascarpone Lemon Buttercream:

1. In the bowl of an electric stand mixer fitted with the whisk attachment, place the softened butter and mascarpone. Cream them on medium speed until smooth and combined, which should take 2-3 minutes.
2. Gradually add the powdered sugar, ½ a cup at a time. Add the lemon zest and a pinch of salt, whisking until well incorporated.
3. If the frosting is too thick, add heavy cream one tablespoon at a time until it reaches the desired consistency.

Assemble the Cake:

1. Top the cooled cake with the lemon mascarpone buttercream, and pour the cooled blueberry sauce on top of the frosting.

This French Cake with Blueberries is a heavenly treat that will impress your guests with its elegant flavors and beautiful presentation. Enjoy the harmonious blend of textures and flavors that make this cake a true delight!