Heat a large nonstick skillet over medium-high heat. Add kielbasa, and cook 2 minutes on each side or until browned. Remove from pan, and keep warm.
. Add oil to pan. Add bell peppers, garlic, and onion; sauté 7 minutes or until lightly browned. Place sausage on top of vegetable mixture, and add beer. Bring to a boil; cover, reduce heat, and simmer 15 minutes or until vegetables are tender. Increase heat to medium-high, and cook, uncovered, 3 minutes or until liquid evaporates.