A Kuchen, of course.
Except when it’s a Torte. Which may be a Tart but definitely not a Pie. Fruit pies are not really a thing in Germany.
So when does the Kuchen end and the Torte start?
It turns out to be easier than I thought. A Torte needs multiple layers. A cake is just one piece, possibly with bits of fruit on top and/or icing.
Fun fact: Germans traditionally bake their Kuchen in a sheet pan and cut them into rectangular portions. If you go to the bakery and get Kuchen, that’s the format they usually come in.