Swiss Tart With Caramelized Onion

Directions

1. 1
   Preheat the oven to 210 Celsius.
2. 2
   Sfit the flour and sugar together and lace into a bowl. Cut in the butter.
3. 3
   Beat the egg, water, and salt together until the salt dissolves. Add to the flour mixture and mix together. Cover the dough in plastic wrap and refrigerate for at least 1-2 hours.
4. 4
   Roll out the dough and place into a pie pan. Prick the surface with a fork, put aluminum foil over the dough and fill with rice or beans for weight.
5. 5
   Bake for 10 minutes, remove from oven, take out the weight, and bake for 5-10 minutes more, until lightly brown.
6. 6
   Lower the oven to 180 Celsius.
7. 7
   Saute the onions in the olive oil until golden. Place in the pie pan.
8. 8
   Mix the eggs, buttermilk, nutmeg, mozzarella, and blue cheese together in a separate bowl. Add salt and pepper and pour over the onions.
9. 9
   Bake for 30-40 minutes, until lightly golden on the top and firm to the touch. Remove from oven, cool 15 minutes, and slice.