Vanilla Custard Cake with Berry Filling

6 cups whole milk, divided

6 egg yolks

1 tablespoon vanilla extract

1 cup sugar

1¼ cups cornstarch

7 T butter, room temperature and cubed

2 cups heavy cream, whipped to medium peaks

Fruit Layer:

3 cups frozen cherries (or frozen berries of choice)

½ cup sugar

3 T cornstarch

½ cup water, divided

Powder sugar, for dusting

2 sheets puff pastry

To make the vanilla custard whisk together the egg yolks and sugar in a bowl until smooth. Whisk in 3/4 cup of the milk. Add the cornstarch, and vanilla. Set aside.

Add the remaining 5 ½ cups of milk into a medium pot and bring to a simmer.

Remove from the heat, and temper about ½ of the hot milk into the egg yolk mixture, whisking vigorously. Return the mixture to the pot. Place the pot on low heat and cook for a few minutes, whisking constantly until thickened. Bring the custard to a boil for 5 minutes, then remove from heat. Whisk in the room temperature butter.

Transfer the custard to a mixing bowl, cover the top with plastic wrap and set aside until completely cold at room temperature.

In three additions, fold in the whipped heavy cream. Keep refrigerated until ready to use.

In a medium pot, combine the cherries, and half of the water. Bring the cherries to a boil. Whisk together the remaining water with the cornstarch to make a smooth slurry. Add the slurry to the boiling fruit, and continue to cook, stirring constantly for 5-8 minutes until the mixture is thick and jammy. Remove from heat and set aside to cool completely.

Preheat the oven to 425°.

Roll each of the two pieces of the puff pastry into 15x11 inch rectangles. Transfer one rolled pastry onto a baking sheet. Use a fork or sharp knife to prick the pastry all over. Bake for 15 minutes until medium golden color. Repeat the baking process with a second puff pastry sheet.

Set the baked puff pastry sheets aside to cool.

Assembly: 

Place the first baked pastry sheet into a deep baking pan (15x11 inches).

Spread half of the vanilla custard evenly over top of the puff pastry.

Spread the fruit filling evenly over the custard and repeat the same steps with the remaining custard.

Top with the last sheet of baked puff pastry, pressing down gently to adhere it into the custard.

Refrigerate the cake for 1-2 hours to set. Dust with powdered sugar before slicing and serving.