1. If using fresh onion and jalapeño, sauté them with oil in a 10-inch ovenproof skillet or large pan over medium heat for 3 to 4 minutes until softened.

2. Add ground beef and cook until browned and no longer pink, breaking it up as it cooks. Drain any excess fat if desired.

3. Stir in chili powder or taco seasoning, cumin, salt, black pepper, onion powder (if not using fresh onion), diced tomatoes with green chilis, and jalapeño if using.

4. Add cauliflower rice and stir to combine. Cook until the mixture reaches a boil, then reduce heat to a simmer.

5. Let simmer for 7 to 10 minutes or until most of the liquid is absorbed and flavors meld, stirring occasionally.

6. Stir in sliced black olives (if using) and about 1 cup of shredded cheese until melted and well incorporated.

7. Sprinkle remaining cheese evenly on top. Place the skillet under the oven broiler or cover the pan to melt the cheese fully, watching carefully to avoid burning.

8. Serve immediately, optionally topped with shredded lettuce, fresh cilantro, sour cream, avocado, or other desired toppings.