Preheat the oven to 350 degrees. Prepare a 9x13 casserole dish with nonstick cooking spray.
In a large skillet over medium-high heat, add the olive oil. Season the chicken with salt and pepper. Add the chicken to the skillet in batches and brown on all sides.
Transfer chicken to the casserole dish.
In the casserole dish, toss the chicken together with the bell peppers, broccoli, and onions.
In a mason jar or small bowl, mix together the rice wine vinegar, liquid aminos, sesame oil, ground ginger, and chili garlic sauce.
Pour the mixture over the chicken and vegetables, then sprinkle with cashews.
Cover and cook for 30 minutes. Remove the cover and continue cooking for 15 minutes.
Garnish with sliced green onions. Serve over cauliflower rice, if desired.