Step 1: Cook the Rice
Rinse the rice in a fine-mesh sieve under cold water until the water runs clear. This removes excess starch for fluffier grains. Combine the rinsed rice and 2 cups of water in a medium saucepan. Bring to a boil, then immediately reduce heat to low, cover, and simmer for 15-18 minutes. Remove from heat and let it steam, covered, for 10 minutes. Fluff with a fork.

Step 2: Prepare the Teriyaki Sauce
While the rice cooks, make the sauce. In a small saucepan, combine the soy sauce, mirin, sake, brown sugar, rice vinegar, grated ginger, and minced garlic. Whisk together and bring to a gentle simmer over medium heat. In a separate small bowl, make a slurry by mixing the 2 teaspoons of cornstarch with 2 tablespoons of cold water until smooth. Once the sauce is simmering, slowly whisk in the cornstarch slurry. Continue to simmer, whisking constantly, for 2-3 minutes until the sauce has thickened to a glaze-like consistency that coats the back of a spoon. Remove from heat and set aside. (It will thicken further as it cools).

Step 3: Marinate and Prepare the Chicken
Place the cubed chicken in a medium bowl. In a small bowl, mix 1 tablespoon of cornstarch with 1 tablespoon of water to form a paste. Add this to the chicken along with a few grinds of black pepper. Toss until each piece is lightly coated. This cornstarch slurry will help create a light crust and help the sauce cling later.

Step 4: Cook the Chicken
Heat 1 tablespoon of neutral oil in a large skillet or wok over medium-high heat. Add the chicken in a single layer, working in batches if necessary to avoid overcrowding. Let it sear undisturbed for 2-3 minutes until a golden crust forms, then flip and cook for another 3-4 minutes until cooked through. Remove the chicken to a clean plate.

Step 5: Cook the Vegetables
In the same skillet, add a touch more oil if needed. Add the harder vegetables first (like carrots and broccoli). Stir-fry for 3-4 minutes. Add the quicker-cooking vegetables (like snap peas, bell peppers, cabbage) and the white parts of the sliced green onions. Stir-fry for another 2-3 minutes until all vegetables are tender-crisp.

Step 6: Combine Chicken and Sauce
Return the cooked chicken to the skillet with the vegetables. Pour about ¾ of the prepared teriyaki sauce over everything. Toss well to combine and heat through for 1-2 minutes, allowing the sauce to coat every piece and glaze beautifully. Drizzle with the sesame oil and give one final toss.

Step 7: Assemble the Bowls
Divide the fluffy cooked rice among four serving bowls. Spoon the teriyaki chicken and vegetable mixture over the rice. Drizzle with the remaining teriyaki sauce for extra flavor.

Step 8: Garnish and Serve
Garnish each bowl generously with the green parts of the sliced green onions, toasted sesame seeds, and any optional toppings like pickled ginger or shredded nori. Serve immediately while hot