Mix chicken, curry leaves, yogurt, garlic, ginger, chili powder, turmeric, garam masala, salt, coriander, cardamom, and black pepper together. Cover and let marinate in a refrigerator for 2 hours or up to overnight.

Stir cornstarch and rice flour into chicken and yogurt mixture just before frying.

Heat oil in a deep pan over medium heat. Add chicken pieces into the hot oil in batches, and fry, stirring frequently, until browned and crispy, about 5 minutes.

Transfer to a plate lined with paper towels to drain. Repeat with remaining chicken pieces.