Citrus and Red Pepper Sauce

• 150 g leeks
• 2 white onions
• 3 carrots

Roughly chop the vegetables and cut the oranges and lemons into large chunks. In a tilting pan (or a wide heavy-based pot), melt the butter and add the vegetables and oranges and lemons. Fry until softened, then add the paprika. Deglaze with the soya sauce and orange juice. Add the fish bones and simmer for 2 hours.

Strain the sauce and reduce to the desired consistency. This sauce make