Tuna steaks with sweet and sour celery
Heat the oil in a frying pan, add the onion and cook for 3-4 mins.
Add the chopped celery and cook for a further 3-4 mins until beginning to soften.
Stir in the tomatoes and cook over a medium heat until the tomatoes become pulpy.
Add the capers, sugar and vinegar. Turn up the heat and cook until the vinegar has evaporated. Set aside.
Heat a griddle and brush the tuna with a little oil and season.
Place the tuna in the hot pan and cook for about 3 minutes on each side. (1 min each side for rare, 4 mins each side for well done).
Serve the fish topped with the celery mixture and scatter over chopped parsley.
Season to taste.