Preheat your oven to 350ºF with the oven rack in the middle.
Heat your cast iron skillet over medium heat. When the pan is warm, add the avocado oil, onion, ground beef + salt. Cook, breaking up the beef and stirring occasionally, until the beef is almost cooked through and the onions are soft, about 5-10 minutes.
Add in the frozen cauliflower rice to the ground beef, and continue cooking until the cauliflower rice is thawed and all the moisture is absorbed, another 5 minutes. The cauliflower rice will absorb all the flavor of the ground beef, stretching out the amount of meat for a fraction of the cost. Plus, it gets more veggies into the dish! One of my favorite hacks.
Last, stir in 1/4 cup of the enchilada sauce into the ground beef mixture. Take it off the heat, and stir to combine.
Assemble the enchiladas. Start by putting about 1/4 cup layer of the enchilada sauce in the bottom of your 9x13 baking dish. Then, lay out a wrap and spoon on a scant 1/4 cup of the ground beef mixture. Top with 1 tablespoon shredded cheese. Roll it up like a cigar and place it in the baking dish. Repeat with the remaining wraps until your baking dish is full.
Top with about 1/2 cup of enchilada sauce (or more if preferred) and a layer of shredded cheese.
Bake uncovered for 20-25 minutes, until the enchiladas are warmed through and the cheese is melted.
Serve warm topped with desired toppings.
Leftovers will keep in an airtight container refrigerated for at least 5 days, or frozen for at least 6 months.