- Step 1
Place steak in a large glass or ceramic dish. Combine 1 tablespoon of the lime juice, 2 tablespoons oil, chilli powder and garlic in a small jug and season with salt and pepper. Pour over steak and turn to coat. Cover and set aside 10 mins to marinate.
- Step 2
Meanwhile, place avocado in a bowl. Mash with a fork and add remaining lime juice, red onion, tomato and salt and pepper. Stir to combine.
- Step 3
Heat a chargrill over high heat. Cook steak, in batches, for 2 mins each side for medium rare or until cooked to your liking. Transfer to a plate and cover with foil. Set aside for 5 mins to rest. Thinly slice across the grain.
- Step 4
Heat the remaining oil in a frying pan. Add combined capsicum and onion and cook, stirring, for 3 mins or until tender. Transfer to a plate.
- Step 5
Serve tortillas topped with avocado mixture, capsicum and onion, beef, a dollop of sour cream and coriander sprigs.