Beat butter until foamy. Then add vanilla sugar, sugar and eggs. In a separate bowl, mix together the flour and Backpulver (or .25 TL baking powder). Gradually add the egg mixture to the flour mixture.
Preheat oven to 175-200 C. (350 F to 400 F)
Prepare a Tortenbodenform (Tart Pan). Use one with a diameter of 28 cm. Grease tart pan with butter, and then lightly dust it with flour. Gently spread dough into the tart pan.
Bake for 20-25 minutes.
*Feel free to bake more than one at a time. They hold up well for a few days.
To make the strawberry topping:
Cut off stems of the strawberries. Starting from outside edge, arrange strawberries, stemmed side down on the cooked Bödenchen.
Pour 250 ml cold water into a bowl and set aside. In a small saucepan, mix one packet of Tortenguss with sugar. Gradually add cold water, constantly stirring, until smooth. Continue constantly stirring and bring liquid to a boil. Remove from heat as soon it boils and pour over strawberries starting from the middle, working your way out to the edge. Leave to cool until liquid solidifies.