Pat the chicken breast dry and cut into bite-sized cubes, then season with sea salt and black pepper.
Toss the chicken in cornstarch until each piece is lightly and evenly coated.
In a small bowl, whisk together the coconut aminos, rice vinegar, honey, minced garlic, and grated ginger to create the sauce.
Heat the avocado oil in a large skillet or wok over medium-high heat until shimmering.
Add the chicken to the pan in a single layer and sear until golden brown and crispy on all sides, about 5-6 minutes.
Add the sliced bell peppers, broccoli florets, and pineapple chunks to the skillet, stir-frying for 3-4 minutes until the vegetables are tender-crisp.
Pour the sauce over the chicken and vegetables, tossing constantly for 1 minute until the glaze thickens and coats everything beautifully.
Serve immediately while the chicken is hot and the vegetables are bright.