Zwiebelkuchen is a popular German onion pastry. It is served with Federweissen (a new fermented wine). Those two just go hand in hand.
I developed my own recipe for this onion pastry. The crust can be bought, Puff Pastry dough (Pillsbury) can be found in the freezer isle.
2 sheets puff pastry dough (in the freezer isle).
Defrost the dough, but it needs to be still cold. (40 min)
12 slices bacon, cut into 1/4-inch strips, fried and pulled apart. Skip the bacon if you are vegetarian
6 cups chopped or thinly sliced onions (1.3 lb.)
4 beaten eggs
1 1/2 cups sour cream
2 cups of Le Gruyere, or other melt cheese like gouda, fontina or provolone
2 tbsp of corn starch (or flour)
1 teaspoon salt
2 dashes of pepper
Some Caraway seeds and nutmeg to taste
Fry bacon until crisp; drain most of bacon fat. Cook onion in remaining bacon fat until tender. Let cool. Combine remaining filling, with ingredients with bacon and onion, eggs at the end. Pour cold filling on puff pastry.
Bake at 350 degrees until almost set, about 45 minutes. Let stand 10 minutes. Enjoy
You need a deep pan to fry your Onions, here are some to choose from: