In a large nonstick skillet, saute onions, red peppers, and Jalapenos in 1 tablespoon butter for 3-5 minute until soft and tender. Remove from heat and keep aside covered in a bowl to keep warm.
Sprinkle beef with salt and pepper and Shape into two oval patties and place in the same skillet, cook over medium=high heat for 3-5 minutes on each side or until juices run clear; drain. Remove and keep warm.
Spread remaining butter over one side of each slice of bread and Place in the same skillet, buttered side down, place the cheese on the other side and toast until lightly browned. Layer the sandwich with one layer of bread and cheese, Onion mixture and another slice of bread.