Method
 

1. Pre-heat the oven to 200°C: 400°F: Gas 6

2. Melt or butter and cook the onion until transparent.

3. Add 225g (8oz) of chopped rhubarb, season with pepper and salt and continue to cook gently for 5 minutes.

4. Allow to cool slightly then add breadcrumbs and stir well

5. Place the mackerel fillets flat, skin side down and spread the stuffing on them.

6. Roll each up, securing with butchers string or cocktail sticks.

7. Place them in a greased oven-proof dish and bake for 15-20 minutes.

8. Place the remaining 450g (1lb) of chopped rhubarb, sugar, water and the grated lemon rind in a saucepan, and stew the rhubarb for 10-15 minutes or until cooked and soft

9. Liquidise or sieve the cooked rhubarb to make a puree.

10. This can be served either hot or cold with the cooked mackerel.