Step 1:
Make the marinade: Stir the chicken, onion, garlic, salt, and pepper in a medium bowl until the chicken is evenly coated. Cover bowl with cling film and refrigerate, 4 hours to overnight.
Step 2:
Heat oil in a deep fryer or large skillet to 171 degrees C
Step 3:
While the oil is hot, make the dough: Whisk together cornmeal, flour, sugar, pepper, and salt in a large bowl.
Gradually beat in cold water until the mixture resembles a smooth pancake batter. Use tongs to remove the chicken from the marinade to beat the dough; Stir to coat the chicken completely. Discard the sauce.
Step 4:
In batches, fry chicken in hot oil for 4 minutes. Transfer chicken to a cooling rack.
Step 5:
Heat up to 190 degrees C
Step 6:
In batches, re-fry chicken in hot oil until golden brown and crispy, 3 to 4 minutes. Transfer to wire rack to drain oil.
Step 7:
Sprinkle with cheese powder and mix well, serve with O'food chili sauce.