Preheat the oven to 200 ° C and grease a baking sheet.
Beat the butter with sugar and vanilla sugar until creamy. Stir in the eggs one at a time. Mix flour with baking powder and stir in with the almonds, bitter almond oil and milk. Smooth the dough on the baking sheet. Bake the cake on the middle rack for about 15 minutes.
Mix the icing sugar with lemon juice or water to make a topping and brush the cake with it. Sprinkle on the sprinkles and let the icing set.
To serve, first cut the cake in half lengthways and crossways. Then cut through each piece crossways and lengthways, and finally divide each rectangle created in this way diagonally to create triangles.