Heat the oil in a large non-stick frying pan over medium-high heat. Cook the onion, stirring, for 2 mins or until onion softens. Add beans. Cook, stirring, for 3 mins or until tender. Transfer to a bowl.
Add the chicken to the pan. Cook for 3 mins each side or until golden and cooked through. Add the dressing and kecap manis and bring to the boil. Reduce heat to medium-low. Transfer chicken to a plate. Return the bean mixture to the pan. Simmer for 1 min or until heated through. Season.
Meanwhile, combine the ancient grains rice, black rice and peas in a large microwave-safe bowl. Cook in the microwave on high for 3 mins or until heated through. Season.
Add the rice mixture to the bean mixture and toss to combine. Divide among serving bowls. Top with the chicken to serve.
Serve with black sesame seeds and white sesame seeds