Warm the skillet: Heat the oil in a large skillet over medium-high heat. Make sure it’s hot before adding the meat to get good browning.
Brown the beef: Add the ground beef and break it up.
Cook until mostly browned with some crisp edges, about 5–6 minutes. Drain excess fat if needed, but leave a little for flavor.
Add aromatics: Stir in the onion and bell pepper. Cook until softened, 3–4 minutes.
Add garlic and cook 30 seconds until fragrant.
Season well: Sprinkle in chili powder, cumin, paprika, oregano, salt, pepper, and red pepper flakes if using. Stir to coat the meat and veggies.
Sauce it up: Pour in salsa (or tomatoes) and broth. Stir and let it simmer 2–3 minutes until slightly thickened.
Add low-carb veggies: Fold in zucchini and riced cauliflower.
Cook another 3–4 minutes, stirring, until the zucchini is tender but not mushy and the cauliflower rice is warmed through.
Cheesy finish: Reduce heat to low. Sprinkle cheese evenly over the top, cover the skillet, and let it melt for 1–2 minutes.
Brighten: Squeeze in lime juice, taste, and adjust salt or spice as needed.
Top and serve: Finish with cilantro and your favorite toppings like sour cream and avocado. Serve as-is, over shredded lettuce, or with low-carb tortillas.