Ingredients:
1 tablespoonfinely grated fresh ginger
1 garlic clove, finely grated
3 tablespoonssoy sauce, preferably dark
2 tablespoonsdry sake
1 tablespoonmirin
2 teaspoonsgranulated sugar
8 boneless, skinless chicken thighs (about 3 pounds), cut into 2-inch pieces, or 3 pounds chicken wings, flats and drumettes separated, or 3 pounds firm winter or summer squash, cut into 2-inch pieces
Vegetable oil, for frying
1 cuppotato starch (katakuriko) or cornstarch
1 cupall-purpose flour
1 teaspoonkosher salt
1 teaspoonfreshly ground black pepper
Lemon wedges, cucumber slices, Japanese mayonnaise preferably Kewpie, Shichimi Togarashi, and your favorite hot sauce(s), for serving
Directions:
Toss chicken, ginger, garlic, sake, mirin, soy sauce and sugar together in a large zip-top freezer bag set inside a large bowl, until chicken is well coated in marinade. Toss chicken pieces in marinade to coat. Cover and refrigerate for at least 2 hours and up to 12 hours.
Pour oil into a large heavy pot fitted with thermometer to come halfway up sides. Heat over high until thermometer registers 300°F.
Whisk potato starch, flour, salt and pepper together in a large bowl until completely combined. Working with a few pieces at a time, dredge chicken in starch mixture, turning to coat and packing into crevices. Shake to remove excess and transfer to a large plate. Working in batches, fry chicken, moving pieces occasionally and adjusting heat to maintain temperature, until just starting to brown, about 4 minutes per batch. Chicken will not be fully cooked through. Transfer to a sheet tray lined with paper towels to drain. If using very large chicken wings or drumsticks, you may need to add 2 to 4 minutes to the fry time, the crust should be a pale golden color when it is done with the first fry.
Increase heat until thermometer registers 375°F. Working in batches, fry chicken, moving pieces occasionally and adjusting heat to maintain temperature, until deep golden brown, about 60 seconds per batch. About 90 seconds for larger wings or drumsticks.
Serve hot or at room temperature, with squeeze of lemon and a drizzle of hot sauce with cucumber on the side.