Name: Three Onion Tart
Prep time: 120 min
Yield: 10
Cuisine: Francesa
Ingredients: 2 3/4 cups flour; 1/4 teaspoons salt; 1 egg, beaten; 1 1/2 tablespoons olive oil; 6 tablespoons unsalted butter; 1/3 cups cow's milk , cold; 3 1/2 cups leek, sliced along with the pale green parts; 3 tablespoons olive oil; 1 red onion , slice; 1 cup green onion , chopped; 1 egg; 250 grams Gruyère cheese, grated; Parmesan cheese

Preparation

Medium

Make the pastry for the tart by mixing in the processor the flour, salt, beaten egg, 1 1/2 tablespoons of olive oil, 6 tablespoons of butter, and cold milk. Place the dough in the refrigerator for 30 minutes. Preheat the oven to 180 degrees Celsius (350 Fahrenheit). Roll out the pastry and place it in a tart pan. Bake it for 10 minutes with beans (to maintain its shape). Remove the beans and add Parmesan cheese. Bake for another 15 minutes until golden.