Whisk together the gochujang, tamari, rice vinegar, honey, minced garlic, and grated ginger in a small bowl to create the glaze.
Season the sliced chicken breast evenly with the sea salt and black pepper.
Heat the sesame oil in a large skillet or wok over medium-high heat until it begins to shimmer.
Add the chicken to the skillet and sear until golden brown and cooked through, approximately 5 to 6 minutes.
Remove the chicken from the pan and set it aside, then add the broccoli, bell pepper, and snap peas to the same skillet.
Sauté the vegetables for 3 to 4 minutes until they are crisp-tender and brightly colored.
Return the chicken to the pan and pour the gochujang glaze over the mixture, tossing everything together until thoroughly coated and heated through.
Serve the spicy stir-fry immediately over the warm cooked brown rice.