Mix lemon juice, turmeric powder,pepper powder, and salt.Marinate chicken with this spice mix.
Grind coarsely whole pepper and fennel seeds ,keep it aside.
Heat an iron kadai with coconut oil. Add on sliced onions and green chilies. Let it saute on medium heat till light brown (3-4 mins).
Add in the finely chopped ginger and garlic, mix well for a minute.
Add Kashmiri chilly powder, coriander powder, garam masala, and turmeric powder. Mix well and add salt according to taste.
Add the marinated chicken. Mix well, add vinegar, cover and cook.
Open, and add in the coarsely grinded pepper powder and mix well.
Let the chicken dry roast on low flame for another 5 minutes or until it becomes blackish brown in color.Make sure that you stir/mix it well, so that it does not stick to the bottom of the kadai.
astly sprinkle curry leaves and give a nice stir.Serve Hot.