Preheat the oven to 350°F. Slice the bread in half lengthwise. Spread each piece with 3 to 4 tablespoons of refried beans and top with 3 to 4 tablespoons of grated cheese. Arrange the molletes on a baking sheet as you make them. If you want to add more toppings like ham, turkey, bacon or chorizo, sprinkle them on top of the cheese.
When they are all assembled, bake until the cheese has melted and the bread has a nice toasted crust on the bottom and around the edges, 8 to 10 minutes. Eat while hot. Serve with pico de gallo, or your favorite salsa, on the side.