1. First make the salsa. Preheat the grill. Arrange the chilies on a baking sheet and cook, turning frequently, until blackened and charred. Leave to cool, then rub off the skins with kitchen paper. Halve and deseed the chiles then chop finely.
2. Mix the red and green chilies, tomatoes and coriander together in a bowl. Blend the vinegar and oil together in a jug, season with salt and pour over the salsa.Toss well, cover and chill in the refrigerator until required.
3. Season the steaks with salt and pepper. Brush a griddle pan lightly with oil and heat over a medium heat until hot. Cook the steaks for 2-4 minutes on each side, or until cooked to your liking. Serve immediately with the salsa.
Cook time 35 mins