Ham and Cheese Breakfast Casserole

Butter (for the dish)

loaf sliced white toasting bread

mild cheddar, grated

small tomatoes, or 16 cherry tomatoes, thinly sliced

thick slice (3/4 pound) flavorful baked ham, cut into 1/4-inch dice (About 2 1/2 cups diced)

large eggs

whole milk

Salt and pepper,