Trim off excess fat and skin from the drumsticks. Make 3 or 4 long, deep incisions on each drumstick. Rub with lemon juice and put in the refrigerator for 30 minutes to marinate.
Put the yogurt in a bowl and set aside.
Place a medium nonstick sauté pan over low heat. Add the besan and roast over low heat, stirring continuously, for 4 to 5 minutes or until lightly browned and fragrant.
Let cool to room temperature and transfer to deep bowl. Add the yogurt, ginger paste, garlic paste, turmeric, garam masala, chile powder, salt and chiles.
Add the chicken drumsticks to this mixture and stir well so that the drumsticks are evenly coated. Cover the bowl and put in the refrigerator for 1 to 2 hours to marinate.