Dice the chicken breast into bite-sized pieces and toss them in a bowl with the arrowroot powder, sea salt, and black pepper until evenly coated.
Heat the avocado oil in a large skillet or wok over medium-high heat.
Add the chicken to the skillet and sear until crispy and golden brown on all sides, approximately 5 to 7 minutes, then remove the chicken and set it aside.
In the same skillet, add the sliced bell peppers and snap peas, sautéing for 3 to 4 minutes until they are tender yet still crisp.
While the vegetables cook, whisk together the coconut aminos, rice vinegar, minced ginger, and minced garlic in a small bowl.
Return the cooked chicken to the skillet along with the pineapple chunks and the prepared sauce mixture.
Toss everything together for 1 to 2 minutes over heat until the sauce thickens and beautifully glazes the chicken and vegetables.
Garnish with sesame seeds and serve immediately while hot.