Onion tart with cambozola and olive oil crust

I discovered a great recipe for crust made with olive oil. It's originally intended to make empanadas gallegas, but here I kneaded in a bit of rosemary from the garden and used it for a caramelized onion galette.

Olive oil crust:
2C white flour
1/4C water
1/4C Olive oil
1 egg, beaten
1/4t salt

Instructions: Mix dry ingredients. Mix in wet ingredients. Roll thin, shape and bake. Brush beaten egg over the top before baking to give it a nice shine.

Onion and cambozola tart w/rosemary crust:
1 Olive oil crust with 1-2 table spoons chopped fresh rosemary kneaded in
3-6 onions, halved, then sliced vertically (3 big ones, 6 small ones)
3-4 oz. Cambozola cheese
1 T Brown sugar
2  T balsamic vinegar
2 T Olive Oil
Left over egg wash from olive oil crust (or 1 new egg, beaten)
Salt and pepper to taste

Instructions:
1. Heat olive oil in a large sauté pan or dutch oven over med heat.
2. Add onions and cook until wilting and starting to brown.
3. Add sugar, vinegar, salt and pepper and reduce heat to low. Cook until well caramelized (about 30 min)
4. Roll out olive oil crust in a large irregular circle.
5. Spread onions in a level layer, leaving a crust border of 2-3 inches. Dot with Cambozola cheese.
6. Fold edges of crust over to make a smaller circle. The galette shape in the photo happens naturally.
7. Brush with egg wash.
8. Bake in a 400 deg. oven for 30-35 min.