Season the chicken thigh pieces with salt and freshly ground black pepper. Rub with your hand to make sure they coat the chicken evenly. Let it marinate for 30 minutes
Preheat oil enough to deep-fry the chicken. Place the flour and baking powder in a shallow platter and stir to mix. Place the beaten egg and milk in another shallow platter. Coat the chicken pieces with egg wash and then coat with the flour. Shake off any excess. Fry until golden brown and the chicken is cooked through. Remove and place on absorbent paper towel to absorb extra grease. Keep them warm in the oven while you are frying the rest
Once you are done frying all the chicken pieces, bring the oil back to hot again, add in the basil leaves. They will sizzle and crisp up pretty quickly. Take care not to burn them. Remove with slotted spoon into absorbent paper towel. Gently scatter the crunchy basil leaves on top of the fried chicken and then season with some salt and pepper again and lightly toss them to mix. Serve immediately and be impressed :)