Remove Steak from packaging and brush all over with mustard. Mix oregano, garlic powder and paprika together with some salt and pepper and sprinkle over the steaks. Leave for 30 minutes so steak come up to room temperature. Meanwhile dice tomatoes, red pepper, red onion, garlic and chillies and place in a bowl. Add chopped stalks and leaves of coriander and chopped leaves of parsley along with salt and pepper. Mix well, cover and leave until ready to serve. Heat a griddle pan on a med/high heat until smoking, drizzle steak with oil and add to pan. Cook for 3-4 minutes on each side then transfer to a baking tray and place in an oven set at 180°C/GM4 for 10-15 minutes. Remove from oven and allow to rest for 8-10 minutes. Slice onto serving plate and spoon over the salsa with a squeeze of lime.