In a mixing bowl, combine the chicken cubes with ginger-garlic paste, red chili powder, lemon juice, and salt, massaging until every piece is evenly coated.

Cover the bowl and let the chicken rest in the refrigerator so the marinade fully penetrates the meat.

Whisk the egg into the marinated chicken, then dust in the cornstarch, all-purpose flour, and a pinch of red food coloring, tossing until every piece is thickly and evenly coated.

Heat the oil in a kadai over medium-high heat until it reaches deep-frying temperature and a small piece of batter dropped in sizzles and rises immediately.

Carefully lower the coated chicken pieces into the hot oil in batches and fry, turning occasionally, until pale golden and just cooked through.

Lift the fried chicken out with a slotted spoon onto a wire rack or paper towels and let it rest so the crust sets before the second fry.

Return the rested chicken to the hot oil and fry a second time until deeply golden-red and audibly crisp on the outside.

In a separate pan, heat a spoonful of the frying oil and sauté the curry leaves, chopped garlic, and slit green chilies until the curry leaves turn crisp and fragrant.

Lower the heat and stir the whisked yogurt, soy sauce, and remaining red chili powder into the tempering, mixing quickly into a thick, glossy sauce.

Add the twice-fried chicken to the pan and toss quickly over high heat until every piece is evenly coated in the glossy tempering, then serve immediately.