In a small mixing bowl, whisk together the coconut aminos, rice vinegar, honey, tomato paste, arrowroot powder, minced garlic, and grated ginger until smooth.
Dice the chicken breast into bite-sized pieces 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 sauté until golden brown and cooked through, approximately 5 to 7 minutes.
Remove the cooked chicken from the skillet and set it aside on a plate.
Add the chopped red and green bell peppers along with the snap peas to the same skillet, sautéing for 3 to 4 minutes until they are tender-crisp.
Add the fresh pineapple chunks and return the cooked chicken to the skillet, tossing to combine with the vegetables.
Pour the prepared sauce over the chicken and vegetable mixture.
Cook for an additional 1 to 2 minutes, stirring constantly, until the sauce thickens and becomes glossy.
Serve the stir-fry immediately over the warm cooked brown rice.