• Before You Start: Please note that this recipe requires a resting time of 8 hours or overnight. Now, gather all the ingredients.
  

To Prepare the Ingredients

• Cut 2 green onions/scallions into 2-inch (5 cm) lengths. Peel the ginger knob and thinly cut about 5 slices ginger.
  
• Trim off the excess fat and the white, stringy connective tissue (tendons) from 2 boneless, skin-on chicken thighs.
  
• Score the flesh to open up the meat, cutting the connective fibers at ½-inch (1.5-cm) intervals, especially on the thickest parts. Then, gently pound the flesh with the back of your knife to flatten and make rolling easier. Fill any empty spots with trimmed pieces of meat to create a more even surface.
  

To Roll the Chicken

• Turn the chicken sideways (90 degrees) and start rolling tightly from the bottom edge. Roll parallel to the direction that you scored the meat; the skin is now on the outside.
  
• Tie the roulade snugly with butcher twine. For the best shape, don't tie it too tightly. Don't tie it too loosely, either, or your roll will fall apart. You can use your favorite method; below are two ways.
  
• Method 1: Tie one end with twine and make a knot; loop and tie it twice more to secure. Then, wrap the twine around the roll, spacing each wrap ½ inch (1.5 cm) apart. Tuck the twine around the last wrap a few times instead of tying it.

  Method 2: Cut and tie several pieces of twine around the roll crosswise, spacing each ½ inch apart. I like to tie a final piece of twine lengthwise to finish.

To Cook

• Preheat a pot just big enough to hold the chicken rolls over medium-low heat. Then add 2 tsp neutral oil. When the oil is hot, place the rolled chicken in the pot, seam side down.
  
• Sear the skin without moving it for about 2 minutes until the seam is set. Occasionally, carefully roll the chicken without tearing the skin.
  
• Sear until all sides are evenly browned, about 10 minutes. Turn off the heat and use a paper towel to wipe away any excess fat.
  
• Pour 1 cup water into the pot and gently scrape the browned bits off the bottom using a wooden spatula.
  
• Add ½ cup mirin, ½ cup soy sauce, ½ cup sake, and 2 Tbsp sugar.
  
• Stir the seasonings with the spatula. Add the ginger slices and green onion.
  
• Bring it to a boil over medium heat.
  
• Once boiling, cover with a lid and simmer over medium-low heat for about 7–8 minutes.
  
• Remove the lid and flip the chicken. Now, place a drop lid called otoshibuta on the meat. See my What is Otoshibuta post to learn why we use it and how to make one at home; or you can buy one on Amazon. Simmer for an additional 6–7 minutes (you don't need to cover with the pot's lid).
  
• Increase the heat to medium-high and continue simmering, basting the chicken with the sauce until it thickens and develops a glossy glaze, about 5 minutes.
  
• Remove the ginger and green onion.
  

To Marinate Overnight

• Transfer the chicken and all the braising liquid to a storage container.
  
• Let it cool, cover, and refrigerate overnight to allow the chicken to soak up the sauce for the best flavor. I like to add peeled boiled eggs to the marinade to make ramen eggs.
  

To Serve

• After 8 hours, remove from the marinade and cut off the twine with kitchen shears.
  
• Cut the chicken chashu roll crosswise into ½-inch (1.5-cm) slices. For the best flavor, I like to sear the surface with a culinary butane torch until lightly charred. Serve as is, as a ramen topping, or in a rice bowl with heated braising sauce drizzled on top.
  

To Store

• Transfer the chicken chashu and eggs out of the marinade to a new airtight container. You also can save the marinade in a separate jar or container to drizzle on your chashu rice bowl. Store in the refrigerator for up to 7 days or up to 1 month in the freezer. Defrost overnight in the fridge before reheating. To reheat, you have three options: 1) Soak the chashu slices in hot cooking sauce, 2) directly add it to your bowl of ramen or hot noodle soup, or 3) sear using a kitchen torch.