Make tikka masala dip. Whisk together yogurt with ketchup, garlic, lemon juice, salt, cumin, paprika, chili powder, turmeric, sugar, ground ginger, and black pepper. Let sit for 20 minutes.
Meanwhile, prepare chicken nuggets. Cut chicken into bite-size chunks and place in a food processor. Pulse until chicken is finely chopped.
Combine the spices in a medium bowl including garlic powder, cumin, paprika, salt, black pepper, ground ginger, coriander, turmeric, and cayenne. Set aside half. With the remaining half, combine the spice mixture with ground chicken and beaten eggs.
Slowly add water to the chicken while mixing constantly. Once all of the water is incorporated, mix vigorously with chopsticks or a fork for 1 minute. Shape chicken into 25 chicken nuggets.
Place 1 cup flour in a shallow bowl. Place remaining ¾ cup flour in another shallow bowl along with cornstarch, baking powder, and reserved spice mixture, stirring to combine. Add 1 cup water and whisk until combined. If the batter is too thick, add 1-2 more tablespoons of water.
Coat the chicken nuggets in flour, then dip in the batter, making sure to cover both sides.
Heat enough oil in a large pan to come up the sides 2 inches high. Bring to 350 degrees F.
Carefully drop the chicken nuggets in the frying oil and cook until golden brown, about 3 minutes. Flip and cook on the other side until golden brown, another 2-3 minutes. Remove chicken nuggets from the oil with a slotted spoon and drain excess oil on paper towels.
Serve chicken nuggets with tikka masala dip.
Notes
You can use ground chicken instead of grinding it yourself.The tikka masala dip can be prepared the day before.