Spinach, Feta, and Caramelized Onion Quiche

Saute onions in butter on medium-to-low heat until caramelized (about 30 minutes). Add spinach. Cook and stir until spinach wilts and most of the moisture seems gone. Set aside.

Whisk together eggs and sour cream until creamy. Stir in feta and vegetable mixture, and tomatoes if desired. Pour into pie crusts (do not defrost first if frozen). Bake on cookie sheet on middle rack for 40 minutes or until tops are beginning to be golden brown and crusts are golden brown.

Let stand for 5 minutes or so, then eat.