Preheat your broiler. Cut the peppers in half lengthwise, remove the stems, and scoop out the seeds. Rub the insides and outsides with a little oil, then place on a lined baking sheet.
Broil for 3-4 minutes per side, until softened slightly. If any char forms on the skin, allow the peppers to cool and then rub it off with your thumbs.
Dice the onion and garlic and set it aside.
Prepare the cauliflower rice (I saute the frozen kind straight from a bag over low heat, stirring occasionally, until warmed and beginning to brown). Slice the lime and avocados.
Prepare the Chicken
Cut the chicken into bite sized pieces & season with salt and pepper.
Heat oil in a large skillet over medium heat, then add the chicken in, stirring occasionally. Once the chicken begins to brown, add the onion to the pan and sauté together for another 5 minutes.
Stir in the fajita seasoning and tomatoes and bring to a simmer. Allow it to cook together for about 2-3 minutes, then remove it from the heat.
Assemble the Stuffed Peppers
Spoon the chicken into the peppers with prepared cauliflower rice, your favorite salsa, and sliced avocado, and enjoy!