Cream of Onion Soup

Preparation:
Preheat oven to 350°. Spread garlic cloves on a sheet pan lightly coated with olive oil and bake until very soft, about 10 minutes. Set aside. Melt butter in a 4-quart saucepan. Slowly cook onions until caramelized and golden brown,about 30 to 40 minutes, stirring frequently to prevent sticking. Add leeks and scallions. Cook an additional 10 to 15 minutes. Add garlic and deglaze with white wine. Add stock and simmer for 30 minutes.
Remove from heat. Add chives. Let cool slightly. Transfer to blender container and puree while adding sour cream, salt and pepper.