Place cornstarch in a shallow bowl. (Start with about ¾ cup and add more if needed.) Dredge chicken on both sides and set on a plate.
In a small container combine tamari or soy, water, honey, grated ginger and garlic. Mix and set aside.
Place oil in a skillet on medium-high heat. Salt and pepper chicken and then gently add it to oil and cook for 3 minutes per side. Remove from skillet.
Turn heat to medium and carefully pour the sauce into the pan. Scrape mixture with a wooden spoon or spatula for about 30 seconds.
Carefully add the chicken back to the pan. Cook another 1 minute per side or more if needed and turn off heat.
Remove chicken to a cutting board and slice into ½-inch pieces.
Portion rice on plates and place chicken slices on top. Sprinkle with sesame seeds and green onions, if desired.
