Pat the chicken breast dry with a paper towel and cut into 1-inch cubes, then season evenly with sea salt and black pepper.
Heat the avocado oil in a large skillet or wok over medium-high heat until it begins to shimmer.
Add the chicken cubes to the pan in a single layer and sear without moving for 3 minutes to develop a crust, then flip and cook until golden and crispy on all sides.
Remove the chicken from the pan and set it aside on a plate; add the broccoli, bell peppers, and snap peas to the same pan.
Stir-fry the vegetables for 3 to 4 minutes until they are tender-crisp and the colors are vibrant.
In a small glass bowl, whisk together the tamari, honey, red chili flakes, rice vinegar, sesame oil, minced ginger, and minced garlic to create the glaze.
Return the crispy chicken to the pan with the vegetables and pour the sweet-chili sauce over the entire mixture.
Toss everything together for 1 to 2 minutes over medium heat until the sauce thickens and coats every piece of chicken and vegetable beautifully.