Mix the seasoning: In a small bowl, combine chili powder, cumin, smoked paprika, oregano, onion powder, cayenne, salt, and pepper.
Set aside.
Prep the chicken and veggies: Slice chicken thinly against the grain. Slice bell peppers and onion into strips. Mince garlic.
Pat chicken dry to help it brown.
Season the chicken: Toss chicken with half the seasoning blend and 1 tablespoon of oil. Let it sit while you heat the pan.
Sear the chicken: Heat a large skillet over medium-high heat with 1 tablespoon of oil. Add chicken in a single layer.
Cook 4–6 minutes, stirring once or twice, until cooked through with browned edges. Transfer to a plate.
Cook the peppers and onions: Add 1 tablespoon oil to the same pan. Add peppers and onion with a pinch of salt.
Cook 5–7 minutes, stirring occasionally, until tender-crisp and slightly charred at the edges. Stir in minced garlic and the remaining seasoning. Cook 30–60 seconds until fragrant.
Return chicken to the pan: Add the chicken back and toss with the peppers and onions.
Squeeze in the juice of half a lime. Taste and adjust salt, pepper, or lime as needed. Keep warm on low.
Cook the cauliflower rice: In another skillet, heat 1 tablespoon oil over medium.
Add cauliflower rice with a pinch of salt and pepper. Cook 4–6 minutes (fresh) or 6–8 minutes (frozen) until hot, tender, and fluffy, not soggy. Squeeze in a little lime and stir in chopped cilantro if using.
Assemble the bowls: Divide cauliflower rice into bowls.
Top with the chicken fajita mixture. Add avocado, salsa, Greek yogurt or sour cream, shredded cheese, jalapeños, and extra lime wedges.
Serve and enjoy: Finish with a drizzle of hot sauce or an extra sprinkle of smoked paprika for color.