In a mixing bowl, combine the orange juice, rice vinegar, brown sugar, soy sauce, minced onion, orange zest, sriracha, cornstarch, grated garlic, and grated ginger. Whisk everything together until well combined.
Cut the boneless, skinless chicken breasts into bite-size pieces. This helps the chicken cook evenly and absorb the flavors of the sauce.
Place the chicken pieces in the crockpot and pour the prepared sauce over them. Make sure the chicken is well-coated in the sauce.
Cover the crockpot and set it to cook on low for 6-8 hours or on high for 3-4 hours. The longer you cook it on low, the more tender the chicken will be.
If you prefer a thicker sauce, about 30 minutes before serving, remove the lid and let it cook uncovered. This will allow the sauce to reduce and thicken.
Once the chicken is cooked through and tender, serve it over rice or noodles. Drizzle some of the sauce on top and garnish with additional orange zest or green onions if desired.
