Marinate Chicken: Put ¼ - ⅓ cup soy sauce and 6 boneless, skinless chicken thighs in a large bowl or storage bag (use up to ½ cup soy sauce, if needed); toss to coat. Let marinate for 15-30 minutes.
Prep: Preheat outdoor grill to a medium-high heat and clean grill grates.
Broccoli: Place the 2 cups broccoli florets in a large bowl and toss with 1 tablespoon extra virgin olive oil and a generous sprinkle of kosher salt.
Grill: Remove the chicken from the soy sauce, allowing excess liquid to drip off. Season chicken with kosher salt & ground black pepper. Place directly on the hot grill grates and let cook for 2-4 minutes. Flip chicken and place the prepped broccoli on the grill on a grill pan or large piece of aluminum foil sprayed with nonstick cooking spray. Let the chicken cook for another 2-4 minutes or until the internal temperature reaches 162℉. During the last 2 minutes of cook time for the chicken, brush on some teriyaki sauce. Toss the broccoli a few times during the cooking process and remove when cooked to your desired crispness. Remove all the chicken and broccoli when they are fully cooked.
Rest: Let the chicken rest on a plate or cutting board for 5-10 minutes, then cut into strips or bite-sized pieces.
Rice Bowls: Divide the rice, cucumbers, carrots, edamame, cabbage, avocado, green onion, chicken, and broccoli between bowls.
Serve: Enjoy the rice bowl with a drizzle of the remaining teriyaki sauce!
Storage: leftovers can be kept in an airtight container for 3-4 days. Be sure to keep hot items separate from cold ingredients to make reheating easier.