To your sliced chicken, add your lime juice, 1 tsp salt, 1 tbsp oil, fajita seasoning and diced jalapeno. Mix well, cover and leave to marinade for 1 hour (at room temperature).
Heat 3 tbsp oil over medium-high heat. Add your peppers and onions and 1 tsp salt. Fry for 15 minutes or so, stirring frequently, until nicely caramelised, translucent and sweet. Add your garlic and fry briefly. Add your chicken and any marinade/juices. Fry until the meat has gathered a little colour. Deglaze with the beer and reduce until sticky (if necessary).
Load into wraps with a good tbsp cheddar. You should have enough for 8 wraps. Wrap up with 6 or so folds. Place, folded side down, on a baking tray and sprinkle over some remaining cheese.