Add the chicken pieces to a large bowl and combine with ginger-garlic paste, lemon juice, salt, turmeric powder, red chili powder, cumin powder, coriander powder, garam masala, and chaat masala. Mix well and let the chicken marinate for at least 30 minutes to allow the flavors to develop.
Add besan, rice flour, kasoori methi, chopped cilantro, green chilies, and baking soda to the marinated chicken. Mix until the chicken pieces are evenly coated.
Add cold water a little at a time until the mixture forms a thick coating around the chicken. The batter should cling to the chicken without becoming runny.
Heat oil in a deep kadai over medium heat until it reaches about 350°F (175°C).
Carefully drop the coated chicken pieces into the hot oil, frying in small batches to prevent overcrowding.
Cook for 6 to 8 minutes, turning occasionally, until the pakoras are golden brown, crisp, and the chicken is fully cooked.
Remove the chicken pakoras using a slotted spoon and transfer them to a wire rack or paper towel-lined plate to drain excess oil and serve hot with mint chutney.