Heat your pan and add olive oil. Add in diced chicken breast and 1/2 a packet of fajita seasoning. Mix so all the chicken is coated in the spice mix and let cook, stirring occasionally.
Slice up onion and capsicum. Once chicken is cooked remove it from the pan and add in the vegetables, mince garlic and the rest of the fajita seasoning. Mix and let cook until soft.
In a bowl mash avocado, lemon juice and salt.
Heat up tortillas in the microwave then add sautéed vegetables, chicken, avocado mash, greek yoghurt and coriander.
Enjoy!