Begin by microwaving the frozen cauliflower rice as directed on the package; open the vent and set aside.
In a skillet over medium heat, cook the diced onion with olive oil for about 5 minutes until soft.
Add the cauliflower rice, drained tomatoes with chiles, garlic powder, cumin, and chili powder to the skillet. Mix thoroughly and cook for another 5 minutes to blend flavors.
Taste and season with salt and pepper as needed.
Serve warm, and store leftovers in the fridge for up to 3 days.
Notes
Feel free to adjust seasoning to taste. This dish is quick, healthy, and perfect for a low-carb meal.