Preheat oven to 425F and line a large baking sheet with parchment paper (or grease it).

Cooking the rice. Bring 2 cups water to a boil in a medium saucepan. Stir in the rice and salt, cover and reduce heat to low. Simmer for 15 minutes or until all of the water is absorbed. Set aside to cool down when ready.

Making the sauce/marinade. Measure 1/2 cup cold water and pour 1 1/2 tsp tapioca flour directly into the measuring cup and stir gently until well dissolved. Then, pour into a small saucepan, stir in 1/3 cup tamari, 1/3 cup maple syrup, 1/4 cup rice vinegar, 1 tsp garlic powder, and 1/2 tsp ginger powder. Bring to a boil, constantly stirring, then lower the heat to medium and stir until the sauce thickens and easily coats a spoon (it takes from 3 to 5 minutes).

Baking. Place the chicken thighs, pineapple slices, and broccoli florets on your baking sheet, then pour about 1/3 cup sauce on the boneless chicken thighs. Flip and turn the thighs until well coated with the sauce. Bake for 20-25 minutes or until the internal temperature of the chicken thighs reach at least 165F. (Tip: You could also marinate the chicken into the sauce for 2 to 8 hours before baking)

Assembling the bowls. Remove the baking pan from the oven and slice the chicken thighs. Place some rice in the bowls, then arrange some chicken, pineapple slices, and broccoli florets on top of the rice. Top with additional sauce, sesame seeds, and chopped green onion when ready to eat.