• Before You Start…Please note that this recipe requires 30 minutes of marinating time. 

  Gather all the ingredients.
  

To Marinate the Chicken

• Prepare 1½ lb boneless, skin-on chicken thighs by cutting each into 2-inch (5-cm) pieces. Season with ½ tsp Diamond Crystal kosher salt and freshly ground black pepper.
  
• Now, grate the ginger (I use a ceramic grater) and measure ½ tsp ginger (grated, with juice). Add it to a large bowl. Mince or press 1 clove garlic (I use a garlic press) and add it to the bowl.
  
• Add ½–1 Tbsp soy sauce, ½ Tbsp sake, and ½ tsp toasted sesame oil to the ginger and garlic. Whisk to combine.
  
• Add the chicken to the marinade and mix it with your hands. Cover and marinate in the refrigerator for 30 minutes.
  

To Preheat the Oil

• While the chicken is marinating, prepare the oil for deep-frying. Pour about 4 cups (960 ml) neutral oil into a heavy-bottomed pot (I use a Dutch oven) and heat it to 325ºF (160ºC) over medium heat.
  

To Coat the Chicken

• Meanwhile, dredge the chicken pieces. Prepare separate piles of 2 Tbsp all-purpose flour (plain flour) and 2 Tbsp potato starch or cornstarch in a tray.
  
• Lightly coat a piece of marinated chicken in the flour and dust off the excess. Next, dredge it in the potato starch and shake off the excess. Place it in a separate tray.
  
• Continue with the remaining chicken pieces.
  

To Cook: The First Fry

• Check that the oil temperature has reached 325ºF (160ºC). Tip: If you don‘t have an instant read thermometer, insert a wooden chopstick into the oil; you‘ll know it‘s hot enough if small bubbles start to appear around the tip. For more helpful tips, see my post How to Deep-Fry Food.

  When it's ready, gently add 3 to 5 chicken pieces at a time to the hot oil. Do not overcrowd the pot. Tip: If you add too many pieces at once, the oil temperature will drop quickly, and the chicken will absorb too much oil.
  
• Deep-fry for 90 seconds, or until the chicken is a light golden color. Transfer to a wire rack to drain the excess oil. Tip: If the chicken browns too quickly, then the oil temperature is too high. Either put a few more pieces of chicken in the oil or lower the heat setting. Controlling the oil temperature at all times is very important for deep-frying.
  
• The residual heat will continue to cook the chicken as it rests. Continue to fry the remaining chicken pieces. Between batches, scoop up and discard the crumbs in the oil with a fine-mesh sieve. This keeps the oil clean and prevents it from becoming darker.
  

The Second Fry

• Now, raise the oil temperature to 350ºF (180ºC). Place the first 3 to 5 pieces of rested chicken back into the oil and deep-fry for 45 seconds, or until the skin is golden brown and crispy. Transfer them to the wire rack to drain the excess oil. Continue frying the remaining chicken pieces.
  
• The left photo shows the chicken pieces after the first fry and the right photo shows them after the second fry. The chicken pieces on the right are slightly darker in color.
  

To Serve

• Serve the chicken hot with lemon wedges and a dipping plate of Japanese Kewpie mayonnaise. You can also sprinkle shichimi togarashi (Japanese seven spice) on the mayo for a bit of spice, if desired.
  

To Store

• Let it cool completely and transfer to an airtight container. You can store it in the refrigerator for up to 3 days and in the freezer for up to a month.