Place oil in medium nonstick frying pan over medium-high heat. When oil is hot, add onions and cook until soft and browned around the edges. Add chile and sweet corn. Sauté until heated through. Transfer to plate and set aside.
Top each of 2 bread slices with 2 slices white cheddar, 2 slices meatloaf arranged to cover bread, a good-sized dollop of mashed potatoes spread to cover meat, and half the corn, green chile and caramelized-onion mixture. Top each with 2 slices of the yellow cheddar and 1 slice remaining bread.
Heat large cast iron or nonstick skillet over medium-high heat. When hot, place 2 tablespoons of butter in 2 places on the pan. Carefully place sandwiches over butter in pan. Spread tops with remaining butter.
Grill sandwiches a few minutes on each side or until golden brown and cheese melts.
- 1 tablespoon oil
- 1 small onion, sliced in thin rings
- 1 green chile, such as jalapeño, chopped
- Kernels from 1 ear super sweet corn
- 4 large slices sourdough bread
- 4 slices Wisconsin Aged White Cheddar cheese, at room temperature
- 4 1/2-inch to 1-inch thick slices of deli-prepared or homemade meatloaf, warmed
- 1 cup deli-prepared or homemade mashed potatoes, warmed
- 4 slices Wisconsin medium yellow Cheddar cheese, at room temperature
- 4 tablespoons butter, softened, divided