Whisk Up the Savory Sauce: In a medium saucepan, combine the tamari (or soy sauce), water, brown sugar replacement, allulose (or xylitol), sesame oil, minced garlic, ginger, and hot pepper flakes. Bring this mix to a gentle boil over medium heat.
Thicken and Cool: Sprinkle the xanthan gum (or glucomannan) evenly over the boiling sauce and whisk vigorously until it's well combined. Let it continue to boil for 2 to 3 minutes until it thickens slightly. Remove from heat and allow it to cool down completely.
Marinate the Chicken: Place your bite-sized chicken pieces in a bowl. Pour two-thirds of the cooled sauce over the chicken, tossing gently to ensure every piece is coated. Cover the bowl and refrigerate for at least 2 hours to let the flavors meld. Keep the remaining one-third of the sauce separate for serving.
Prepare Skewers (if using bamboo): If you're using bamboo skewers, soak them in water for at least an hour before you start. This simple step helps prevent them from burning on the grill. You’ll need about 6 to 8 large skewers or 12 smaller, appetizer-sized ones.
Get the Grill Ready: Preheat your grill to a medium-high setting and lightly grease the grates to prevent the chicken from sticking. Carefully thread the marinated chicken pieces onto your prepared skewers.
Grill to Perfection: Place the chicken skewers on the hot grill. Cook for approximately 5 to 6 minutes per side, remembering to brush them frequently with the reserved marinating liquid as they cook. Grill until the chicken is beautifully browned and cooked through.
Serve with Flair: Transfer the delicious skewers to a platter. Sprinkle generously with toasted sesame seeds and fresh chopped scallions. Serve immediately with the additional reserved sauce on the side for dipping!