Combine flour, salt and sugar. Add diced butter and rub the butter into the flour until it is crumbly. Using an electric mixer, add the egg and a little bit of water. Form a ball and set in the fridge for at least 30 min.
Roll out the dough in a 9 inches pie pan. Cover bottom of the dough with parchment paper and pastry weights and bake for about 20 minutes on 350F.
Remove the weights and cover the bottom with almond butter or apricot jam.
Preheat oven on 400F
Arrange the apricots on the dough, skin-side down. They should fit tightly next to each other. Sprinkle with vanilla sugar.
Bake for 20-25 Minutes. A couple of minutes before the end sprinkle sliced almonds on top.