Pat the chicken breast dry with paper towels and cut into bite-sized cubes.
In a small bowl, toss the chicken cubes with arrowroot powder, sea salt, and black pepper until evenly coated.
In a separate small jar, whisk together the coconut aminos, rice vinegar, tomato paste, honey, minced ginger, and minced garlic.
Heat the avocado oil in a large skillet or wok over medium-high heat.
Add the chicken to the skillet in a single layer and sear for 3-4 minutes per side until golden brown and crispy.
Add the sliced bell peppers, broccoli florets, and pineapple chunks to the pan, stir-frying for 3 minutes until the vegetables are tender-crisp.
Pour the prepared sauce over the chicken and vegetables, tossing constantly for 1-2 minutes until the sauce thickens into a glossy glaze.
Serve immediately while hot and crispy.