Heat your oven to 190°C/Fan 170°C/Gas 5. Drain the chickpeas, rinse them and then tip them into a roasting tin. Add 1 tbsp olive oil and season with a pinch of salt and pepper. Toss to coat the chickpeas. Slide into the oven and roast for 20-25 mins till the chickpeas are crisp.
Halve the chilli, flicking out the seeds and white bits for less heat, and finely chop. Slide into a bowl. Grate in the lemon zest and squeeze in the juice, and stir well with 1 tbsp oil and a little salt and pepper. Finely shred half the mint leaves. Peel and finely slice the onion. Stir both into the chilli lemon dressing and set aside.
Slice the melon into thin wedges, carving off the peel and scooping out the seeds. Slide into a large mixing bowl. Halve the cucumber. Trim and peel one half and chop it into small pieces. Slice the tomato thinly. Tear the lettuce leaves into rough pieces. Add all 3 ingredients to the bowl and mix.
Pour 1 tbsp oil into a large pan and bring to a medium-high heat. Add the diced chicken leg and a good pinch of salt and pepper. Fry for 6-8 mins, stirring occasionally, until the chicken is golden on all sides and cooked through.
Toss the cooked chicken and crispy chickpeas through the salad, along with the minty onions and dressing. Heap onto plates and finish with the remaining mint leaves and the feta crumbled over the top.