Prepare the sauce by whisking together the coconut aminos, rice vinegar, tomato paste, honey, and arrowroot powder in a small bowl until smooth.
Dice the chicken breast into bite-sized pieces and season evenly with sea salt and black pepper.
Heat the sesame oil in a large skillet or wok over medium-high heat.
Add the chicken to the skillet and sauté for 5-7 minutes until golden brown and cooked through, then remove the chicken and set it aside on a plate.
In the same skillet, add the diced onion, red and green bell peppers, minced ginger, and minced garlic, sautéing for 3-4 minutes until the vegetables are tender-crisp.
Stir in the pineapple chunks and the prepared sauce, simmering for 1-2 minutes until the glaze begins to thicken.
Return the cooked chicken to the pan, tossing thoroughly to coat every piece in the sweet and sour sauce.
Serve the chicken and vegetable mixture immediately over the warm cooked white rice.