Fluffy blueberry cake

Fluffiger Heidelbeerkuchen

Recently I read in a flyer that in a store (do not remember where) blueberries were on offer; I immediately asked my husband to get her. And then I thought about what I can bake with it. Fortunately, my favorite cake – sponge cake – came to my mind, which I usually make with strawberries and cherries from the garden; I had such an appetite for it that I had to do it with purchased culture blueberries. He tasted fantastic. D