Mix the margarine, sugar, vanilla sugar and salt with a whisk until creamy. Add lemon juice (or alternatively 1 bottle of lemon flavor). Then gradually add eggs and stir for no more than 2 minutes.
Mix the flour, cornstarch and baking powder and stir into the margarine, sugar and egg mixture.
Grease a 30-inch loaf pan and sprinkle with breadcrumbs, fill in the dough and bake in a preheated oven at 180 degrees for about 50-60 minutes.
Glaze suggestion:
Mix 250 g of powdered sugar with 2 tablespoons of lemon juice and 1-2 tablespoons of hot water and spread on the toppled cake.