Cut the chicken breast into 1-inch cubes and season with sea salt and black pepper.
In a small bowl, whisk together the coconut aminos, rice vinegar, tomato paste, arrowroot powder, minced ginger, and minced garlic to create the sauce.
Heat the avocado oil in a large skillet over medium-high heat until shimmering.
Add the chicken to the skillet and cook until golden brown and cooked through, approximately 6 to 8 minutes.
Remove the chicken from the pan and set aside, then add the sliced bell peppers and red onion to the same skillet.
Sauté the vegetables until they are crisp-tender, about 4 minutes, then stir in the pineapple chunks.
Pour the prepared sauce into the skillet and stir constantly until the glaze thickens and becomes glossy.
Return the chicken to the pan and toss everything together to ensure an even coating before serving.