Combine the cheddar cheese, cream cheese, sour cream, and chopped jalapeños in a small bowl. Set aside.
Preheat skillet over medium heat. Spread butter on each side of the bread. Place 1/4 of the cheese mixture in each sandwich.
In a large skillet over medium high heat, place the sandwiches. Cook 3 to 5 minutes per side until lightly browned and cheese is melted.
Serve with salsa on the side.
Recipe posted with permission from Cooking for the King, Kosher Recipes With the Taste of Torah, Designed to Bring Majesty to Your Menu, by Renee Chernin