Melt butter in large heavy pot. Add onions and saute over medium heat until translucent, about 8 minutes. Add garlic, flour, oregano and dillweed and cook about 1 minute, stirring constantly. Mixture will have a pasty consistency.

Add sherry and continue cooking and stirring for another minute. Add broth and cream and bring to boil. Reduce heat and whisk in cheese, cooking and whisking until cheese is melted. Add salt and pepper to taste. Serve immediately. Makes about 12 (1-cup) servings.