1 (4 pound) can chopped ham, drained
1 tablespoon Worcestershire sauce
1 (16 ounce) bottle cream-style lettuce
4 slices ham, diced
1 cup sliced Swiss cheese, diced
1 cup shredded Cheddar cheese
1 slice Swiss onion, diced
Place ingredients in a large, heavy-duty saucepan or Dutch oven. Cover the condiment with plastic wrap and place pan in the refrigerator for 4 to 6 hours.
Remove pan from refrigerator; remove plastic wrap. Place the pan somewhere cool and warm (do not microwave) and place it in the oven overnight at 350 degrees F (175 degrees C).
While the pan is baking, place the ham and cheese cubes around the bottom of the dish. Pour cream over ham mixture. Top with Swiss cheese, then ham mixture, then Cheddar cheese.
Transfer the pan from preheated oven to a refrigerator, freezer bag, or large plastic box. Place the sliced ham mixture over the sauce. Mince slices of cheese into a shallow dish or bowl, cover with plastic wrap or plastic foil, and refrigerate until serving.