In a small bowl, whisk together the coconut aminos, rice vinegar, tomato paste, honey, minced ginger, minced garlic, and arrowroot powder to create the glaze.
Cut the chicken breast into 1-inch cubes and season evenly with sea salt and black pepper.
Heat the avocado oil in a large skillet or wok over medium-high heat until shimmering.
Add the chicken to the skillet and cook for 5-6 minutes, turning occasionally until golden brown and cooked through, then remove and set aside.
In the same skillet, add the diced red and green bell peppers and red onion, sautéing for 3-4 minutes until the vegetables are crisp-tender.
Stir in the pineapple chunks and return the cooked chicken to the skillet.
Pour the prepared sauce over the chicken and vegetables, tossing constantly for 1-2 minutes until the glaze thickens and coats everything evenly.
Serve the sweet and sour chicken immediately over the warm cooked white rice.
Garnish the dish with sesame seeds and thinly sliced green onions for a fresh finish.