Heat oil in large saucepan over med. heat. Add celery and garlic, sauté until veggies are lightly cooked (5 min). Reduce heat to low-med. In a separate bowl - Add flour and 1/2 c. half & half, whisk until smooth, then add remaining 1 1/2 c. half & half . Pour into sauce pan & whisk with leaks. Add broth and beer continue to whisk occasionally for 5 minutes. Stir in Worcestershire sauce, mustard, salt & pepper. Add potatoes & cheese, stir constantly until cheese is melted. DO NOT LET SOUP BOIL! Garnish with bacon and green onion. (31 grams carbs in 2 cups)