In a large bowl, combine the hash browns, sausage, bacon, green pepper, 1 cup cheese and onion. Transfer to a greased 13-in. x 9-in. baking dish.
In another bowl, whisk the biscuit mix, salt, eggs and milk; pour over the top. Sprinkle with remaining cheese. Cover and refrigerate overnight.
Remove from the refrigerator 30 minutes before baking. Bake, uncovered, at 375° for 30-35 minutes or until a knife inserted near the center comes out clean. Let stand for 10 minutes before cutting. Yield: 12 servings.