In a large bowl, combine the ground chicken, kosher salt, toasted sesame oil, minced scallions, and shallot. The mixture should feel wet and sticky, which is what you want for forming meatballs. Don’t be afraid to get your hands in there! Kneading will help blend the flavors beautifully.
Next, take your dried shiitake mushroom and use a microplane to grate it directly into the meatball mixture. This step is crucial; it adds a fantastic umami flavor that elevates the dish. Mix everything well until fully incorporated.
Now it's time to get a little hands-on. Knead the mixture very thoroughly with your hands until it becomes sticky and tacky. This texture is important for the meatballs to hold together during cooking.
To test your seasoning, fry up a tiny patty of the mixture. This tasting step is essential to ensure you have the right amount of salt and seasoning. Adjust the mixture if necessary by adding more kosher salt.
Once you’re satisfied with the flavor, cover the bowl with plastic wrap and place it in the fridge for at least one hour, or up to a day if you have time. Chilling the mixture makes it easier to roll out your meatballs, allowing the flavors to meld beautifully.
When you’re ready to cook, preheat your broiler. Position the oven rack so that it’s about 6 inches from the heating element. This height is perfect for getting that crispy, charred exterior on your Tsukune.
Brush a rimmed baking sheet or broiler pan with avocado oil. This will help prevent sticking and create a lovely golden crust on the meatballs.
Using a #40 disher (or about 1½ tablespoons), scoop out the meat mixture and roll them into uniform-sized balls with your hands. If you find the mixture is sticking to your hands, lightly coat them with avocado oil to make rolling easier.
Arrange the meatballs evenly on the greased baking sheet. It’s important to give them space for even cooking and browning.
Broil the meatballs for about 2 minutes. Then, carefully brush them with the All-Purpose Stir-Fry Sauce. Rotate the tray 180 degrees so they cook evenly.
Repeat the basting and broiling process two more times, for a total of about 8 minutes of cooking time. The meatballs should be nicely browned and cooked through, reaching an internal temperature of 165°F to ensure they’re safe to eat.
Finally, remove your Tsukune from the oven and, if desired, sprinkle with toasted sesame seeds for an extra touch of flavor and presentation. Serve immediately and enjoy!