Butter enough bread (crusts trimmed off) to cover a baking dish, buttered sides down.
Slice to cover: tomatoes, 1 onion (if liked), season with pepper.
Sprinkle over 1 cup grated cheese.
Butter enough bread slices to cover, buttered sides up this time.
Beat together 3 eggs, 1 1/2 cups milk.
Pour over and leave to stand 2-3 minutes.
Baked 150C for 45 minutes or until set.