Great dish to be made ahead for a brunch. Can substitute other ingredients as desired
Butter a 9x13 inch baking pan.
In a large bowl combine the bread, onion and parsley. Spread the mixture in the bottom of the prepared pan. Sprinkle with 1 ½ cups of cheddar cheese. Spread mushrooms and Red pepper. Drizzle with butter. In a small bowl beat the eggs with the mustard, salt, seasonings and milk and pour over the vegetable layer. Top with the remaining cheese.
Refrigerate overnight. Bake in a 350 oven for one hour.