Slice the chicken breast into thin, bite-sized strips and season evenly with sea salt and black pepper.
Heat the avocado oil in a large skillet or wok over medium-high heat until shimmering.
Add the chicken to the pan and sear for 5-6 minutes, stirring occasionally, until golden brown and fully cooked through.
Remove the chicken from the pan and set aside on a plate, keeping the remaining oil in the skillet.
Toss the broccoli florets, snap peas, and sliced red bell pepper into the pan and stir-fry for 4 minutes until they are vibrant and tender-crisp.
Add the minced garlic and grated fresh ginger to the vegetables, sautéing for about 30 seconds until the mixture becomes highly aromatic.
Return the cooked chicken to the pan, then pour in the tamari and toasted sesame oil, tossing everything together for 1 minute to glaze.
Transfer the stir-fry to a bowl and garnish with sesame seeds before serving.