Onion goat cheese tart

I made this for Easter. Its definitely not for everyday eatin. It really impresses at a party. Disclaimer: I wouldn't necessarily call this healthy.

Your favorite pie crust dough (mine is the kind you buy but beware, it's full of all sorts of nasty crap)
2 large yellow onions, thinly sliced
1-2 Tbs olive oil or butter
5 Tbs of softened butter
1/2 c plain yogurt
1 c room temp goat cheese (Costco has this cheap!)
2 eggs
1-2 tsp fresh chopped thyme
salt and pepper

Preheat oven to 375
In a large skillet or cast iron pot, cooked sliced onions in the oil over moderate heat. Cover and occasionally stir for 10 minutes or until tender. Uncover and continue stirring until onions are slightly brown and liquid is cooked out.
While onions are cooking, roll out your dough and cut to size of a large tart pan (I like the kind with a removable bottom). Spray the pan with nonstick spray and press the dough into the pan. Prick with holes and bake for 10 minutes or until almost brown (I dont weigh my crust down but you could if you wanted).
Meanwhile wisk the butter, yogurt, goat cheese, eggs, and salt and pepper together until really smooth.
Layer the onions on the bottom of the baked crust. Top with the goat cheese mixture. Sprinkle thyme on top and bake for 20 minutes or so. Cool and eat cold or warm ( I like them a little warm). Yummy!