Take the chicken leg and make slashes on it. Make a paste of the marination ingredients and rub the paste all over the chicken. Keep the marinated for sometime.
Heat oil in a pan. Lay the marinated chicken and shallow fry them in low-medium heat till the chicken is cooked completely on all sides and nicely brown from outside.
Flip over the chicken occasionally for even cooking. It takes approximately 20-25 min. Take out the chicken and keep aside.
In the same oil add the onion and green chillies, curry leaves and saute till onion turns soft.
Add tomatoes and saute till mushy. Add the chilly powder and cracked peppercorns, salt and mix well.
Now add the fried chicken back, stir and mix well and fry for on low-medium heat for about 5 mins and take off the heat.