# What You'll Need:
→ Sourdough Crust
01 - 6 slices sourdough bread, crusts removed
02 - 2 tablespoons unsalted butter, melted
→ Vegetables
03 - 1 cup asparagus, trimmed and cut into 1-inch pieces
04 - 1 cup cremini or button mushrooms, sliced
05 - 1 small shallot, finely chopped
06 - 2 tablespoons olive oil
→ Egg Mixture
07 - 8 large eggs
08 - 1/3 cup whole milk
09 - 1/4 cup heavy cream
10 - 1/2 cup grated Gruyère cheese
11 - 1/4 cup grated Parmesan cheese
12 - 2 tablespoons fresh chives, chopped
13 - 1/2 teaspoon salt
14 - 1/4 teaspoon ground black pepper
# Method:
01 - Preheat oven to 375°F. Grease a 9-inch springform pan or deep pie dish with butter or cooking spray.
02 - Arrange sourdough slices to line the bottom and sides of the prepared pan, overlapping slightly. Brush the bread thoroughly with melted butter. Bake for 8–10 minutes until just crisp, then remove from oven and set aside to cool slightly.
03 - Heat olive oil in a large skillet over medium heat. Add chopped shallot and sauté for 1–2 minutes until fragrant. Stir in sliced mushrooms and cook until softened, approximately 4 minutes. Add asparagus pieces and continue sautéing for 2–3 minutes until tender-crisp. Remove from heat.
04 - In a large mixing bowl, whisk together eggs, whole milk, heavy cream, grated Gruyère, grated Parmesan, chopped chives, salt, and black pepper until thoroughly combined and smooth.
05 - Distribute the sautéed vegetables evenly over the cooled sourdough crust. Carefully pour the egg mixture over the vegetables, ensuring even distribution.
06 - Bake for 25–30 minutes until the frittata is puffed, golden brown on top, and the center is set when tested with a knife. Remove from oven and allow to cool for 5 minutes.
07 - Slice and serve warm or at room temperature, accompanied by fresh green salad if desired.