1. Preheat oven to 450°F. In a seasoned or generously greased 8- to 9-inch cast-iron skillet cook sausage, onion, and garlic over medium-high heat until sausage is brown, using a wooden spoon to break up meat as it cooks. Remove mixture from skillet; drain on paper towels.

2. In a medium bowl combine black beans, tomatoes, cilantro, chipotle peppers, and sausage mixture. In another medium bowl mash pinto beans; spread in the same cast-iron skillet. Top with tomato mixture and sprinkle with cheese.

3. Bake about 15 minutes or until cheese is golden and mixture is bubbly. Serve dip with lime wedges and tortilla chips.

Slow Cooker Directions:

Prepare tomato mixture as directed, using any medium skillet to cook sausage mixture. Spread mashed beans in a 1 1/2-quart slow cooker; top with tomato mixture and sprinkle with cheese. Cover and cook on low-heat setting for 4 hours or on high-heat setting for 2 hours or until bubbly. Serve as directed.