Place almonds in a food processor and process finely. Add sugar, butter, egg, vanilla and flour; mix well.
Roll out the puff pastry and place it in a 9-inch pie plate. Spread the almond-butter mixture within the pastry. Press the apricot halves firmly into the almond-butter mixture in even intervals. Place whole almonds in between the apricots.
Bake until golden brown, around 30 to 40 minutes. Garnish with powdered sugar.