• 1 Spanish onion or 3 medium-sized onions
• ¾ oz. butter

Melt the fat in a deep pan and cook the finely-chopped onion gently for 10 min. Sprinkle and stir in the flour, add the milk and boil. Add the spices and lemon rind; simmer till the onion is just tender. Season and add sherry (if used) before serving.