Slice the chicken breast into bite-sized pieces and season evenly with sea salt and black pepper.
In a small bowl, whisk together the coconut aminos, rice vinegar, and arrowroot powder until the powder is fully dissolved to create the stir-fry sauce.
Heat the avocado oil in a large skillet or wok over medium-high heat until it begins to shimmer.
Add the chicken to the pan and sear for 5-6 minutes, stirring occasionally, until golden brown and cooked through, then transfer to a plate.
In the same pan, add the broccoli, bell peppers, and snap peas, sautéing for 3-4 minutes until they are tender-crisp and bright.
Stir in the minced garlic and grated fresh ginger, cooking for 1 minute until highly fragrant.
Return the chicken to the pan and pour the sauce over the mixture, tossing constantly for 1-2 minutes until the glaze thickens and coats every ingredient.
Remove from heat, drizzle with toasted sesame oil, and garnish with thinly sliced green onions and sesame seeds before serving.