Mexican Open Faced Sandwich

Name: Mexican Open Faced Sandwich
Cuisine: Mexican, Latin American, American
Ingredients: 4 bolillo rolls (or similar crusty bread, like French rolls); 1 cup refried beans (homemade or canned); 1 cup shredded Oaxaca or Monterey Jack cheese; 1/4 cup butter, softened; 1 jalapeño, finely chopped (optional, for heat); Salt and pepper, to taste; 2 medium tomatoes, diced; 1 small onion, finely chopped; 1/4 cup fresh cilantro, chopped; 1 small lime, juiced; Salt, to taste