German Onion Pie

2 large onions, halved and thinly sliced
2 tablespoons butter
1 teaspoon salt
1/4 teaspoon black pepper
1 teaspoon caraway seeds
1 egg
1/4 cup sour cream

Crust:
2 cups all-purpose flour
1 teaspoon baking powder
½ teaspoon salt
5 tablespoons cold butter, cut into small cubes
½ cup milk + 1-2 tablespoons

1. In a large skillet, sauté the onions in the butter over medium heat until they turn translucent and just begin to brown, about 25 minutes, stirring frequently. Pour into a bowl and set aside to cool. Beat the egg and sour cream together and stir into the cooled onion mixture along with the salt, pepper and caraway seeds.
2. Heat oven to 450°F. In a food processor bowl place the flour, baking powder, and salt and pulse to combine. Add the butter and process just until it is the texture of soft crumbs. Add the milk and pulse to form a soft dough.
3. Spray a 10 inch round cake pan with cooking spray and spread the dough out evenly using your fingers. Bring the dough up the sides of the pan. Spread the onion mixture over the dough. Bake for 30 minutes or until lightly browned. Serve warm or at room temperature.