Pat the chicken breast dry with paper towels and season both sides with sea salt and black pepper.
Heat avocado oil in a large skillet over medium-high heat until shimmering.
Place the chicken in the skillet and sear for 5 to 6 minutes per side until golden brown and the internal temperature reaches 165 degrees Fahrenheit.
Remove the chicken from the pan and let it rest for 3 minutes before slicing into thin strips.
In the same skillet, add the sliced bell peppers, snap peas, and red onion, sautéing for 3 to 4 minutes until tender-crisp.
Stir in the minced garlic and grated ginger, cooking for 30 seconds until fragrant.
Whisk together the coconut aminos and toasted sesame oil in a small bowl, then pour the mixture over the vegetables.
Add the sliced chicken back into the skillet, tossing everything together to coat thoroughly in the sauce.
Garnish the stir-fry with sesame seeds and serve immediately while hot.