Combine the sesame ginger simmering sauce, yellow onion and chili garlic sauce in a resealable plastic bag. Place chicken in bag and shake to coat. Let marinate in the fridge 6 - 8 hours or overnight.

Preheat your grill to medium heat.

Remove chicken from the marinade but reserve the marinade.

Place chicken breasts on grill first. Cook, over medium heat, for 5 minutes on each side. Then place the remaining pieces of chicken on the grill. Cook those for 5 minutes on each side. Then cover the grill and continue to cook until the chicken is cooked through, 20 - 25 more minutes.

Cook quinoa according to package directions.

While the quinoa and chicken are cooking, pour the reserved marinade into a skillet and cook over medium-high heat until the sauce reduces by half and the onions are soft. Turn heat to low and keep warm until ready to use.

Once the chicken is cooked through, pour half of the sweet and sour sauce into a bowl. Reserve the remaining sweet and sour sauce for serving.

Use a basting brush to brush the chicken with the sweet and sour sauce. Cover and let cook an additional 5 minutes.

Transfer to a serving plate. Serve alongside reserved sweet and sour sauce and quinoa topped with the reduced mariande.