• Gather all the ingredients. You will also need a pack of 6-inch bamboo skewers.
  

To Prepare the Ingredients

• For the kushikatsu sauce, combine all the sauce ingredients in a small bowl: 4 Tbsp Worcestershire sauce, 2 Tbsp ketchup, 2 Tbsp water, 2 tsp soy sauce, and 2 tsp sugar. Whisk well. Depending on the amount of skewers you‘re preparing, multiply the sauce ingredients as you need.
  
• Boil water in a small saucepan. Gently submerge 9 quail eggs into the boiling water. Cook for 3 minutes and transfer to iced water to let cool. Peel the eggs and set aside.
  
• Put 2 cups panko (Japanese breadcrumbs) in the food processor. Process to make the panko a finer texture.
  
• Snap off the ends of 6 asparagus spears and discard the bottom.
  
• Cut ½ onion into 4 wedges.
  
• Discard the ends of 1 bunch garlic chives (Chinese chives or Nira) and cut them crosswise into 4 equal pieces.
  
• Cut 1 piece boneless pork loin chops (½-inch thick) into 4 pieces and pound the meat with the back of the knife to tenderize the meat.
  
• Cut ½ chicken breast diagonally (which should be against the grain) about ½ inch thick. Then, season with Diamond Crystal kosher salt and freshly ground black pepper.
  

To Skewer All the Ingredients

• Skewer the chicken and pork as if you are stitching, starting from one end of the meat, move the skewer downward and upward alternately.
  
• Equally divide the garlic chives and put them on each end of the 4 pieces sliced pork belly on the cutting board. Roll the garlic chives from one end to the other. Skewer the seam so the pork belly slice will stay in place.
  
• Carefully skewer the 2 sausages and the quail eggs.
  
• For ½ cup sushi ginger (gari), drain it and skewer it as well. For the onion wedges, skewer them toward the core.
  
• Prepare all the skewered ingredients on a plate/tray.
  

To Prepare the Batter

• Whisk 1 large egg (50 g each w/o shell) in a large bowl. Add all but ¼ cup of the 1 cup water, leaving the rest in the measuring cup.
  
• Then, add 1 cup all-purpose flour (plain flour) into the bowl. Whisk all together. With the remaining water, slowly drizzle in water until your batter is the right consistency.
  
• The batter should be runny but thick, and when you dip your finger, it should be covered with the batter. Adjust with more water, if needed. Place the panko in a shallow bowl/tray.
  

To Deep-Fry

• Bring 3½ cups neutral oil to 340–360ºF (170–180ºC). When the oil is hot and ready for deep-frying, you want to start with the vegetables or more plain food first, leaving the meat or strong flavor items for later. That way, the oil stays clean for the vegetables/ plain food, as the oil will turn darker and more flavorful when you start deep-frying the savory food.
• Dredge the ingredients in the batter and then the panko. Remove the excess panko and deep-fry until crisp and golden brown.
  
• Scoop up the panko breadcrumbs between batches to keep the oil clean. Burnt panko will darken your oil, which will change its taste.
  
• Continue with other ingredients. Use a spoon, if you have a hard time coating the batter.
  
• Deep-fry the meat and seafood at the end.
  

To Serve

• Drain the deep-fried food on a wire rack or paper towel. Serve immediately with the kushikatsu sauce and ichimi togarashi (Japanese chili pepper).

To Store

• Keep the leftovers in an airtight container and store in the refrigerator for up to 3 days and in the freezer for up to a month.