Whisk buttermilk and salt, then coat chicken and chill for 4 hours or overnight.
Bring chicken to room temperature and preheat oven to 200°C.
Combine flour, lemon zest, and all spices in a bowl.
Dredge each chicken piece in the spiced flour mixture until coated.
Heat 1cm of oil in an ovenproof frying pan until a breadcrumb sizzles.
Fry chicken pieces skin-side down in batches for 3 minutes per side until golden.
Transfer pan to oven and bake for 15 minutes until juice runs clear.
Drain cooked chicken on kitchen paper and keep warm while finishing batches.
Melt sugar in a pan over high heat until it becomes golden caramel.
Stir in tomatoes and cook for 2 minutes until softened.
Add chillies, sweetcorn, vinegar, and lime juice and cook for 8 minutes.
Stir in parsley and seasoning, then serve alongside the chicken.