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; saut 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.