Caramelized Vidalia Onion Galette - VeryVera

Ingredients

• 1 recipe Mama’s Butter Piecrust
• 4 tbsp. butter
• 3 lb Vidalia onions, cut in half and thinly sliced
• 1 tsp. minced garlic
• Kosher salt
• 1/4 tsp. freshly ground black pepper
• 1 1/2 tbsp. Dijon mustard
• Optional: 1 1/2 teaspoons fresh thyme leaves
• 1 c grated parmesan cheese
• 1 egg, beaten
• Optional: 4 slices bacon, cooked, drained, and chopped
• 2 1/4 c flour or 2 cups AP flour
• 1/3 tsp. kosher salt
• 12 tbsp. (1 1/2 sticks) cold butter, cut in small cubes
• 5 to 7 tablespoons ice water