Pat the chicken breast dry with paper towels and cut into bite-sized pieces.
Toss the chicken in a bowl with arrowroot powder, sea salt, and black pepper until evenly coated.
In a small jar or bowl, whisk together the pineapple juice, coconut aminos, rice vinegar, ginger, and garlic 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 pan 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 on a plate.
Add the broccoli, bell peppers, and snap peas to the same skillet, adding a splash of water if needed to steam, and sauté for 4-5 minutes until tender-crisp.
Return the chicken to the skillet and pour the sauce over the mixture.
Stir constantly for 1-2 minutes until the sauce thickens into a glossy glaze that coats the chicken and vegetables.