Wonderful casserole to make the night before holidays or when you have company. Serve it with fresh fruit salad and muffins or other breads. My DH and son don't care for green pepper, so I just put half of it in the one side of the casserole. Also, due to variations in oven temps, cooking time could be any where from 30 to 50 mins. This recipe was from the Taste of Home web site and I adapted it for our tastes.
In a large bowl, combine the first five ingredients; stir in 1 cup cheese. Transfer to a greased 13x9-in. baking dish.
In another bowl, whisk eggs, milk, baking mix, salt and pepper until blended; pour over top. Sprinkle with remaining cheese. Refrigerate, covered, overnight.
Preheat oven to 375°. Remove casserole from refrigerator while oven heats. Bake, uncovered, 30-35 minutes or until a knife inserted near the center comes out clean. Let stand 10 minutes before cutting.