To make the sauce, pulse the garlic and ginger in a food processor fitted with the metal blade until finely chopped. Add the gochujang, rice vinegar, soy sauce, honey, and fish sauce and pulse just until combined. Pour the sauce into a large mixing bowl and set aside.
In a deep fryer or large, deep stockpot, heat 3 inches of canola oil over high heat to 340°F.
Set a wire rack over a rimmed baking sheet for draining the chicken. Submerge a frying basket in the oil, or place a wire mesh colander nearby. Place a rimmed baking sheet near the fryer. (You’ll shake the fried chicken over the baking sheet.)
Put 2 cups of the rice flour in a shallow bowl (I thought 1 cup was more than enough). In a bowl, stir the remaining 2 cups of rice flour with the water to make a very thin paste (this is also more than you’ll realistically need).
Dredge the chicken pieces in the flour, then dip them into the flour paste to coat. Once all pieces have been coated, carefully place the chicken in the hot oil. Fry for 10 minutes (see note below regarding fry time). Maintain a frying temperature of 340°F.
If using the frying basket, lift it from the oil and vigorously shake the basket over the baking sheet, allowing the crispy bits of batter to fall off. Let the chicken rest in the basket out of the oil for 2 minutes.
If using a colander, use a spider or a slotted spoon to transfer the chicken to the colander and shake vigorously over the baking sheet, allowing the crispy bits of batter to fall off. Let the chicken rest in the colander for 2 minutes.
Check the temperature of the oil; it should remain at 340°F throughout the frying process. Return the shaken, rested chicken to the oil and fry for 10 minutes longer (see note below regarding fry time).
Drain the chicken on the wire rack. Add the pieces to the bowl with the sauce and toss to coat evenly with the sauce.