Rinse the rice and cook it in 400 ml (1 2/3 cups) of water: bring to a boil over high heat, cover, simmer on low for 15 minutes and rest 5 minutes.
Whisk the soy sauce, honey, rice vinegar, ginger, garlic, cornstarch and 80 ml (1/3 cup) of water in a jug until no lumps of cornstarch remain.
Heat the oil in a large skillet or wok over medium-high heat until shimmering.
Add the chicken pieces in a single layer and cook, turning once, until browned and cooked through to 74°C (165°F), about 7 minutes.
Add the broccoli, carrots and 2 tbsp of water, cover with a lid and steam over medium-high heat until the broccoli is bright green and tender-crisp, about 3 minutes.
Stir the sauce again, pour it into the pan and stir constantly until it bubbles and turns thick and glossy, about 1 minute.
Serve over the rice and sprinkle with sesame seeds and sliced green onion.
Tips
Stir the sauce right before adding it; the cornstarch settles.