Step 1Cut each chicken thigh crosswise into three pieces. In a medium bowl, prepare the yakitori sauce by combining the soy sauce, mirin and sake. Set aside 3 tablespoons in a separate bowl. Add the chicken pieces and marinate, refrigerated, for 20 to 30 minutes.
Step 2Soak the bamboo skewers in water at least 20 minutes. Start a two-stage fire on the grill, mounding the hot coals to one side of the grill (this will be the hot side of the fire).
Step 3Remove the chicken from the marinade (reserve the marinade for brushing on the chicken during grilling). Thread the thigh pieces onto the skewers, a couple of pieces at a time, one skewer at the top and one at the bottom of each piece for greater control while grilling.
Step 4Grill the skewers over a medium-high flame, turning occasionally and moving from the hot side of the grill to the cool side as necessary to avoid flare-ups. Just before the meat is done, brush the meat lightly with a little of the reserved marinade.
Step 5Cook until the chicken is cooked through but not dry, about 10 minutes total. Remove to a platter and serve.
Chicken thighs with green onions: Follow the recipe for chicken thighs with yakitori sauce, but thread green onions on the skewers as well. Place a chicken thigh piece on a cutting surface and place a chunk of green onion in the center, where the thigh bone had been. Thread this onto a pair of skewers, one at the top and one at the bottom. Repeat, using up all of the chicken.
Chicken breast with wasabi paste: Cut boneless, skinless chicken breasts into chunks, thread them onto skewers and salt lightly. Grill over a medium fire until they're done, about 5 minutes. Dot each chunk with a spot of wasabi paste (you can also use ume paste or yuzu paste).
Pork belly: Japanese markets usually offer pork belly sliced in two thicknesses -- just like bacon. Use the thicker slices of pork belly, cutting each slice into squares, then threading the squares onto skewers. Sprinkle them with salt and grill over a hot fire until they're browned and crisp, about 7 minutes. If the fire starts to flare up, move the skewers to the cool side of the grill until the flare-up dies down.
Pork belly with shiso: Use the thinner slices of pork belly. Cut them into 1-by-2-inch rectangles and fold them around pieces of shiso leaf. Thread them onto skewers. Salt and grill over a hot fire until browned and crisp, about 7 minutes. If the fire starts to flare up, move the skewers to the cool side of the grill until the flare-up dies down.
Pork belly with enoki mushrooms: Pull the enoki into bundles of half a dozen or so mushrooms and trim off the bottom parts. Cut thin slices of pork belly into rectangles and wrap them around the enoki bundles. Thread them onto skewers. Salt and grill them over a hot fire until browned and crisp, about 7 minutes. If the fire starts to flare up, move the skewers to the cool side of the grill until the flare-up dies down.
Bacon and cherry tomatoes: Cut each strip of bacon in thirds lengthwise. Wrap each bacon piece around a cherry tomato and thread them onto skewers. Grill over a medium fire until browned and crisp, about 10 minutes. If the fire starts to flare up, move the skewers to the cool side of the grill until the flare-up dies down.
Shishito peppers: Thread the peppers onto skewers. Grill over a medium fire until they're softened and slightly charred, about 8 minutes. Moisten the bottom of a platter with soy sauce and place the pepper skewers on top. Cover with a handful of shaved, dried bonito flakes (katsuobushi).
Fresh shiitake mushrooms: Remove the stems from the mushrooms and thread the caps onto skewers; if the caps are very large, they may be halved or quartered before skewering, though it's not necessary. Brush with the yakitori sauce from the chicken thigh recipe and grill over medium-high heat until the mushrooms show grill marks and are tender, about 5 minutes.