Transfer to a bag (or an airtight container) and refrigerate for 1 to 3 hours.
Drain the chicken in a colander, then let it sit at room temperature for about 30 minutes.
Coating & Double Frying
Heat the oil to about 160°C.
frying oil
Beat the egg.
1 egg
Dip the chicken pieces into the beaten egg.
Coat well in flour, then in potato starch.
flour, potato starch
Fry for about 6 minutes at 160°C, turning halfway through if needed (about 3 minutes in), then remove.
Increase the oil temperature to about 180°C, then fry again for about 3 minutes, until the coating is crisp and golden.
Serve immediately, piping hot.
Notes
Pricking the chicken with a fork really makes a difference: the meat turns out more tender and absorbs the marinade better. A spiked meat tenderizer works even better.
Keep the coating thin: too thick a layer gives you more of a KFC-style result than classic Famichiki.