Chipotle chiles, tomatoes, and beer add vibrant flavors to the sauce. Serve over mashed potatoes.
Preheat oven to 350°.
Sprinkle lamb with salt and pepper. Heat a large Dutch oven over medium-high heat. Coat pan with cooking spray. Add lamb; cook 8 minutes, browning on all sides. Remove lamb from pan; set aside. Add onion to pan; sauté 5 minutes or until golden brown. Add broth; cook until liquid evaporates, scraping pan to loosen browned bits. Stir in chiles and the next 5 ingredients (through beer). Return lamb to pan; bring to a boil. Cover and bake at 350° for 1 hour and 15 minutes or until lamb is tender. Sprinkle with cilantro.