In a small bowl, whisk together the coconut aminos, rice vinegar, tomato paste, honey, minced ginger, and minced garlic to create the sauce.
Cut the chicken breast into bite-sized cubes and season with sea salt and black pepper.
Heat the sesame oil in a large skillet or wok over medium-high heat.
Add the chicken to the skillet and cook until browned on all sides and cooked through, approximately 5-7 minutes.
Remove the chicken from the skillet and set aside.
In the same skillet, add the diced bell peppers and red onion, sautéing for 3-4 minutes until crisp-tender.
Add the pineapple chunks and the cooked chicken back into the skillet.
Pour the sauce over the mixture and toss well, simmering for 2 minutes until the sauce thickens and coats everything evenly.
In a separate pan, lightly sauté the cauliflower rice for 3-5 minutes until tender.
Serve the sweet and sour chicken over the warm cauliflower rice.