Heat oil in a 10-inch, straight-sided skillet over medium-high heat; cook onion 5 minutes or until softened. Add garlic and next 4 ingredients; cook, covered, over medium heat 10 minutes. Stir in salt and pepper. Add cod to skillet; reduce heat until wine mixture just simmers. Cover and poach 5 to 7 minutes or until fish flakes with a fork. Serve in bowls with broth spooned over fish.