Nutella Chocolate Mousse Tart

3/4 cup Nutella

1/3 cup unsalted butter

4 eggs separated

1 tablespoon sugar

Makes 1 large tart shell in pan with removable bottom

1 1/2 cups all-purpose flour

1/4 cup unsweetened cocoa powder

1/2 cup sugar

1/2 teaspoon salt

1/2 cup (1 stick) chilled unsalted butter cut into small pieces

2 large egg yolks

2 tablespoons heavy cream chilled

1/2 teaspoon pure vanilla extract

3 egg whites from large or jumbo eggs at room temperature

1/4 cup superfine sugar

1/4 teaspoon cream of tartar

Nutella Chocolate Mousse

In a double boiler or oven proof bowl, over simmering water, melt the Nutella and butter, stir to combine. Beat in the egg yolks, one at a time, stirring after each addition. Remove from the heat and set aside.

In large bowl, beat the egg whites until soft peaks form, then add the sugar and continue beating until smooth and glossy. Gently fold in 1/4 of the egg whites to the Nutella mixture using a spatula, then add the remaining whites and combine completely. Spoon into cooled pie crust and cool in the refrigerator 4 hours.

Dough

Place flour, cocoa, sugar, and salt in the bowl mix together with electric heavy duty mixer. Add butter, mixture will resembles coarse meal, about 10 seconds. Add yolks, cream, and vanilla; process until mixture comes together, keep adding cream if too dry, a little at a time.

Turn out dough onto a piece of plastic wrap, and flatten into a disk with the palm of your hand. Wrap well, refrigerate at least 30 minutes or until ready to use, up to 2 days.

Line the bottom of a removable tart pan with pistachio nuts. Unwrap dough, roll the dough out about 1/2 thick on the clear wrap, lift still on the wrap and place on over the nuts, to line the tart pan. With plastic wrap push still over the top, press sides in to make sure all dough is in the fluted edges to the top. Remove plastic wrap. Prick the dough with a fork on the bottom and bake on 350 until tart is done around 25 minutes. I make sure the toothpick is clean in the center before removing from the oven. Cool around 5 minutes, loosen edges if they look stuck with a knife and gently move from the fluted edges then flip onto on board to cool. Then line a cookie sheet with wax paper and flip it right side up. Fill when cooled with mousse, add a toasted meringue- or whipped cream topping and chopped hazelnuts.

In a chilled clean bowl, beat the egg whites at high speed with an electric mixer until soft peaks form. With mixer running, add the cream of tartar, then gradually add the sugar, a tablespoon at a time, and beat until stiff peaks form. But don't walk away and overbeat as I did! It will not be smooth and get dry as you see in the picture…don't even answer the phone! That's what happened to me and this is the result too stiff of peaks formed! Pile on to the top of your pie and seal edges to crust. (Sprinkles with nuts after its sealed and starts to brown or they will sink in.) Bake at 400°F until lightly browned. Watch this closely as it will brown quickly in different ovens.