Begin by dicing the chicken breasts into bite-sized pieces and placing them in a bowl. Add sesame oil, soy sauce, hoisin sauce, minced garlic, and grated fresh ginger, mixing well to ensure the chicken is fully coated. Heat a large skillet or wok over medium-high heat and cook the chicken for about 10 minutes, stirring frequently until it’s golden brown and fully cooked through.

If you’re starting with uncooked rice, prepare it using your preferred method. Aim for about 15 minutes cooking time, so it’s fluffy but not mushy. If using pre-cooked rice, ensure it's cold, ideally stored in the fridge overnight—it will yield the best fried rice texture. Set the rice aside as you move to the next steps.

In a small mixing bowl, combine light mayo, soy sauce, rice vinegar, and Dijon mustard. Whisk these ingredients until the mixture is smooth and well incorporated, creating a delicious mustard dipping sauce. Cover and refrigerate this sauce to allow the flavors to meld while you continue preparing the Hibachi Chicken.

Using the same skillet, reduce heat to medium and add a drizzle of olive oil. Toss in thinly sliced carrots, halved mushrooms, chopped yellow onion, and zucchini. Sauté these colorful vegetables for about 5 minutes, stirring occasionally, until they are tender-crisp and vibrant.

In the same skillet with the vegetables, toss in butter and let it melt. Add minced garlic and sauté briefly until fragrant, then introduce the cooked rice and a splash of soy sauce. Create a well in the center of the rice to scramble in a whisked egg, folding everything together after the egg is cooked, and stir in sliced green onions for added freshness.

To serve your delightful Hibachi Chicken, spoon a generous portion of the fried rice onto each plate. Top it with the sautéed chicken and vibrant vegetables. Finish by drizzling the chilled mustard sauce on the side.