Preheat broiler. Slice each roll in half horizontally. Brush cut sides of rolls with the 2 tablespoons butter. Place rolls, cut sides up, on a baking sheet. Broil 5 inches from the heat for 1 to 2 minutes or until golden brown; set aside.
In a large skillet cook chorizo over medium heat until brown, using a wooden spoon to break up meat as it cooks. Drain well on paper towels; set aside.
Spoon refried beans into a small microwave-safe bowl. Microwave on 100 percent power (high) about 1-1/2 minutes or until heated through, stirring once.
In a medium bowl combine eggs, milk, chili powder, and salt. Beat lightly with a fork. In a large nonstick skillet melt the 1 tablespoon butter over medium heat. Add egg mixture and chorizo; cook for 2 to 3 minutes or until egg mixture is cooked through but still glossy and moist, lifting and folding the mixture with a spatula as needed while cooking.
Spoon refried beans on the cut sides of the roll halves; spread beans evenly. Place roll halves on a baking sheet. Top beans with scrambled eggs, avocado slices, and cheese. Broil 5 inches from the heat for about 3 minutes or just until cheese is melted and bubbly.