How to Make It
Melt butter in a Dutch oven over medium. Add onion, celery, fennel, and garlic, and cook, stirring often, until tender, about 5 minutes. Add undrained oysters. Cook, stirring constantly, until hot, 3 to 4 minutes. Stir in stock, flour, salt, pepper, and mace. Gradually add cream, stirring constantly. Continue cooking over medium, stirring constantly, until mixture is heated and oyster edges curl. Stir in sherry. Top with chopped parsley.