Start by peeling and slicing the sweet potato into thin strips. Next cut the onion and the aubergine into long strips as well. Now place the sweet potato, aubergine and onion together into a small bowl.
Mix together the olive oil and fajita seasoning, pour the seasoned oil over the vegetables and toss well.
Preheat a large frying pan over a high heat. Sauté the vegetables until they are tender, but are still crunchy, for around 6 to 8 minutes.
Warm up the tortillas in the microwave and serve with the vegetables, iceberg lettuce, guacamole and Alpro Greek Style Plain. You can finish off by seasoning it with parsley and a small amount of salt and pepper.