Cheese Steak Panini with Caramelized Onions

Heat a medium skillet over medium-low heat. Add the butter and 1 tablespoon olive oil. Add the sliced onions and cook slowly until caramel-colored. Salt to taste. Spoon caramelized onions into a small dish and set aside. Add the sliced steak to the skillet and saute to heat through.

To assemble the panini, spread mayonnaise on one side of each slice of bread. Divide the onions, meat and cheese between the two sandwiches. Top with remaining bread. Heat a panini press or pan on medium-low and lightly grease with olive oil. Cook panini until bread is lightly browned and cheese is melted. Slice in half and serve immediately.