Heat the oil in a frying pan over a moderate heat and cook the capsicum, onion and garlic for about 15 minutes, until the capsicum is tender. Transfer to a small bowl and set aside.
Toss the beef with the seasoning mix.
Return the pan to the heat and add a little more oil if needed. Increase the heat to high and cook the beef in batches for 3-5 minutes until well coloured. Transfer the beef to a serving bowl.
Heat the tortillas either in the microwave or a toasted sandwich press.
Serve tortillas for self-assembly with capsicum, beef, sour cream and the fresh herbs.
