Cut the chicken breast into bite-sized 1-inch cubes and season with sea salt and black pepper.
In a small bowl, whisk together the coconut aminos, rice vinegar, grated ginger, minced garlic, and arrowroot powder to create the sauce.
Heat the avocado oil in a large skillet or wok over medium-high heat until shimmering.
Add the chicken to the skillet and sear until golden brown and cooked through, about 5 to 6 minutes, then remove and set aside.
In the same skillet, add the bell peppers and red onion, sautéing for 3 to 4 minutes until they are tender yet still slightly crisp.
Stir in the pineapple chunks and cook for another minute to warm them through.
Return the chicken to the pan and pour the sauce mixture over the ingredients.
Toss everything together for 1 to 2 minutes until the sauce thickens into a glossy glaze that coats the chicken and vegetables.