Heat your oven to 200°C/Fan 180°C/Gas 6. Scrub the potatoes. Slice them into chips about 1 cm wide. Pop them in a bowl. Drizzle with olive oil. Season. Toss to mix. Spread them out on a baking tray. Bake for 30-40 mins till cooked through and golden.
Slice the chicken fillets into strips as big as your little finger. Pop in a bowl. Grate or pare the zest from the lemon. Juice it. Add both to the chicken with 1 tsp of the cumin. Season with salt and pepper. Put to one side for 10 mins.
Peel and finely slice the onion. Rinse and halve the pepper. Scoop out the seeds and white bits. Finely slice it. Heat a glug of olive oil in a wok or deep frying pan. Add the onion and pepper. Stir-fry for 5 mins till soft and charred. Season with a little salt and pepper.
Pop the veg on a plate. Add the chicken and marinade to the pan. Stir-fry for 5-8 mins till golden and cooked through. Add to the veg.
Halve the avocado. Scoop out the stone with a teaspoon. Peel or scoop the flesh from the skin. Slice into strips.
Wash the salad leaves. Dry in a salad spinner or with kitchen paper. Wipe the frying pan clean with kitchen paper. Put it on a low heat. Add a wrap. Fry for 30 seconds to warm through. Flip and fry for 30 seconds more. Slide onto a plate. Repeat with a second wrap.
Pile the salad, onion wedges, pepper, avocado and the chicken into the wraps. Roll up. Serve with the chips and any extra veg on the side.