Place buttered, trimmed, bread slices in the bottom of a 9 x 13 pan, overlapping each other – butter side up. Layer the grated sharp cheddar cheese, meat(s), mushrooms, chilies, and jack cheese.
Mix in a separate bowl the eggs, milk, paprika, basil, pepper, onion salt, and dry mustard.
Pour egg mixture over the layered ingredients. Cover with foil and chill overnight.
In the morning, remove the foil and bake at 325° for 1 hour, or until center is firm and does not jiggle. Depending on your oven, you may need to cook an additional 5 mintues.