Heat your oven to 190ºC/Fan 170ºC/Gas 5. Line 2 baking trays with baking paper. Scrub the sweet potatoes and cut into chips about the same size as your index finger. Spread out on one of the trays. Season the veg with salt and pepper and toss with 2 tbsp olive oil. Set aside.
Mix the breadcrumbs with a pinch or two of cayenne (it's spicy, so add as much or as little as you like), 2 tsp of the oregano and some salt and pepper. Place on a plate. Beat the egg in a shallow bowl.
Pull the skin off the chicken thighs. Dip the chicken in the egg, then in the breadcrumbs to coat them. Arrange on the second baking tray.
Place both trays in the oven, with the chicken on the top shelf, for 40-45 mins. Swap the trays over for the final 15 mins and turn the chips so they cook evenly. Both the chicken’s crust and the chips should be golden.
Check that the chicken is cooked by piercing the largest piece – the juices should run clear and the meat should be white.
Tip the salad into a bowl. Add 2 tsp olive oil and some salt and pepper. Toss to mix. Serve the chicken with the sweet potato chips and the salad.