3 medium leeks (white and light green parts only), thinly sliced
8 large eggs
1 cup mushrooms, sliced (cremini or button)
½ cup half-and-half
1½ cups shredded cheese (such as Gruyère, Swiss, cheddar, or a mix) – 1 cup for the egg mixture and ½ cup for topping
1–2 teaspoons fresh thyme leaves (or ½ tsp dried)
2 tablespoons olive oil or butter
Salt and freshly ground black pepper, to taste
Directions
Prep the leeks: Trim off dark green tops and root ends. Slice leeks lengthwise, then thinly slice crosswise. Rinse thoroughly in a bowl of cold water to remove grit. Drain well.
Sauté vegetables: Preheat oven to 375°F (190°C). In a 10–12 inch oven-safe skillet, heat olive oil or butter over medium heat. Add leeks with a pinch of salt. Cook 5–7 minutes until soft and lightly caramelized. Add mushrooms and thyme. Cook another 5–7 minutes until mushrooms release moisture and begin to brown. Season with pepper and adjust salt if needed.
Make egg mixture: In a large bowl, whisk together 8 eggs, 1/2 cup half and half, 1 cup shredded cheese, pinch of salt and pepper.
Assemble: Reduce heat to medium-low, pour eggs mixture evenly over the vegetables in the skillet. Gently stir once to distribute fillings evenly. Cook undisturbed for 2-3 minutes until edges begin to set.
Bake: Sprinkle remaining 1/2 cup cheese evenly on top. Transfer skillet to oven and bake 15-20 minutes, until center is just set (slightly jiggly is perfect, it will continue cooking as it rests).
Rest & serve: Let rest for 5-10 minutes before slicing. Garnish with extra fresh thyme if desired!
