Add the oil, fajita mix, and tomato purée to a large sauce pan and cook on a medium heat for a few minutes.
Add in the rice and coat well in the sauce.
Add the salt and top with the water. Bring to the boil then cover and cook on a low light until all the water has absorbed (20 mins).
Turn off the heat and leave covered to sit for 10 minutes (makes it fluffier).
Serve immediately topped with guac and sour cream or 5% Greek yogurt.