Chop the onion, green pepper, and mushrooms. Sauté in butter or olive oil over medium heat until softened. Set aside.

Brown the sausage or your preferred substitute. Drain excess grease, if needed, and set aside.

Place both pie crusts in the oven and bake for 10-15 minutes, or until light golden brown. Remove and set aside.

In a mixing bowl, combine eggs and milk. Whisk thoroughly until fully blended.

Evenly distribute the sautéed vegetables and cooked protein between both pie crusts. Pour equal portions of the egg and milk mixture into each crust, and add one handful of cheese to each crust, or adjust to taste.

Gently stir ingredients in each crust to evenly distribute filling without spilling.

Bake for approximately 30 minutes or until a fork inserted into the center comes out clean. Allow pies to cool slightly before slicing and serving.