In a small bowl, whisk together chili powder, cumin, garlic powder, onion powder, smoked paprika, salt, and pepper to create the fajita seasoning.
In a large skillet or wok, heat 1 tablespoon of olive oil over high heat until shimmering.
Add the steak strips in a single layer and sear for 2-3 minutes until browned; remove steak from skillet and set aside.
Add the remaining 1 tablespoon of olive oil to the same skillet over medium-high heat.
Add the bell peppers and onions; sauté for 5-7 minutes until the vegetables are tender-crisp and slightly charred.
Return the steak to the skillet, sprinkle with the fajita seasoning, and toss for 1-2 minutes to incorporate flavors.
In a separate skillet or microwave, steam the cauliflower rice for 3-5 minutes until tender.
Squeeze fresh lime juice over the steak and vegetable mixture and stir in chopped cilantro.
Divide the cauliflower rice into four meal prep containers or bowls and top with the steak and pepper mixture.
Garnish with avocado slices immediately before serving.