Chargrilled tuna with tomato and onion dressing

Ingredients:
olive oil, for drizzling
½ onion, peeled and diced
2-3 tbsp tomato ketchup
1 tbsp fresh tarragon, chopped
splash Worcestershire sauce
salt and freshly ground black pepper
1 tbsp fresh coriander, chopped
1 tuna steak

Preparation:
1. Heat a non-stick griddle pan until hot and drizzle with olive oil.
2. Place the onion, tomato ketchup, tarragon, Worcestershire sauce and seasoning into a bowl and whisk together.
3. Gradually add a drizzle of olive oil and stir in the coriander. Set aside.
4. Chargrill the tuna steak in the hot pan for 1-2 minutes on each side (or according to personal taste).
5. Serve the tuna steak on a serving plate and drizzle with the onion and tomato dressing.