- Sauté onion in butter in a stockpot over medium-low heat. Add crab, warmed half and half, and cream.
- Season with Worcestershire sauce, salt, pepper, and a dash of mace or nutmeg, if desired. Stir in a teaspoon or more cornstarch into milk and add if thickening is needed. Add roe and ¼ cup sherry.
- Serve hot with additional sherry to taste.