Pat the chicken breast dry with paper towels and cut into 1-inch bite-sized cubes.
In a medium bowl, toss the chicken cubes with arrowroot powder, sea salt, and black pepper until every piece is thoroughly and evenly coated.
In a small glass jar or bowl, whisk together the pineapple juice, coconut aminos, rice vinegar, honey, minced ginger, and minced garlic to create the sauce.
Heat the avocado oil in a large non-stick skillet or wok over medium-high heat until shimmering.
Add the chicken to the skillet in a single layer, leaving space between pieces to ensure they sear rather than steam.
Cook the chicken for 6-8 minutes, turning occasionally, until golden brown and crispy on all sides, then remove from the pan and set aside.
In the same skillet, add the sliced bell peppers and sugar snap peas, sautéing for 3-4 minutes until they are tender but still retain a bright color.
Pour the prepared sauce into the skillet with the vegetables and bring to a gentle simmer for about 1 minute until the liquid begins to thicken into a glaze.
Return the crispy chicken to the skillet and toss quickly to coat every piece in the sweet and sour sauce.
Remove from heat immediately, garnish with sesame seeds, and serve warm.