Pat the chicken breast dry with a paper towel and toss in a bowl with arrowroot powder, sea salt, and black pepper until evenly coated.
In a small glass jar, whisk together the coconut aminos, rice vinegar, honey, grated ginger, and minced garlic to create the stir-fry sauce.
Heat the sesame oil in a large cast-iron skillet or wok over medium-high heat until shimmering.
Add the chicken to the skillet in a single layer and sear for 3-4 minutes per side until golden brown and crispy.
Remove the chicken from the pan and set aside, then add the red bell pepper and snap peas to the same skillet.
Sauté the vegetables for 3 minutes until vibrant and tender-crisp, then stir in the fresh pineapple chunks.
Pour the sauce over the vegetables and simmer for 1 minute until it begins to bubble and thicken slightly.
Return the crispy chicken to the skillet, tossing everything together to glaze, and serve immediately over the warm cooked brown rice.