Preheat your oven to 375°F (190°C).

In a large skillet, heat olive oil over medium heat. Add diced onion, mushrooms, and butternut squash. Sauté for 5-7 minutes until tender.

Add chopped kale to the skillet and cook for another 2-3 minutes until the kale is wilted. Remove from heat and let cool slightly.

In a mixing bowl, whisk together eggs, milk, and a pinch of salt and pepper until frothy.

Place the pie crust in a 9-inch pie dish. Spread the sautéed vegetable mixture evenly across the bottom. Pour the egg mixture over the vegetables and sprinkle cheese on top.

Bake in the preheated oven for 35-40 minutes or until the top is golden brown and the filling is set.

Allow to cool for 5-10 minutes before slicing and serving warm.