Preheat the broiler to high heat. Heat a broiler-proof nonstick skillet over medium heat. Spread the cut sides of the rolls with the ghee and broil until golden brown, about 3 minutes. Spread 2 tablespoons of the pizza sauce over each piece of bread. Top with a thick layer of refried beans and shredded cheese. Broil for 2 to 3 minutes, until the cheese has completely melted.