In a large skillet over medium-high heat, cook the ground beef, breaking it up with a spatula as it browns. Cook for 7–10 minutes, or until the beef is fully browned and no pink remains. If there is a lot of grease in the pan, carefully spoon off most of it, leaving just a little for flavor.
Season the cooked beef lightly with salt and black pepper if using. Stir in the condensed cream of mushroom soup until the meat is well coated and the mixture looks creamy and saucy.
Add the cauliflower florets directly into the skillet with the beef and soup mixture. Stir well so the cauliflower is evenly coated and tucked into the saucy beef. The mixture will look thick; that’s okay, as the cauliflower will release some moisture as it bakes.
Stir in 1 cup of the shredded cheddar cheese until it’s evenly distributed through the beef and cauliflower mixture. This helps bind everything together and adds extra richness.
Transfer the mixture to the prepared baking dish or spread it out evenly in your oven-safe skillet. Press it down gently so there are no big air pockets.
Sprinkle the remaining 1 cup of shredded cheddar cheese evenly over the top to create a good, solid layer that will melt and brown in the oven.
Cover the dish tightly with foil and bake for 20 minutes to help the cauliflower steam and soften. Then remove the foil and continue baking for another 15–20 minutes, or until the cauliflower is tender when pierced with a fork and the top is bubbly and starting to brown around the edges.
For a deeper browned, slightly crispy cheese topping like in the photo, switch the oven to broil for 2–3 minutes at the end, watching closely so the cheese doesn’t burn.
Let the skillet casserole rest for about 5–10 minutes before serving. This short rest helps the juices settle so each scoop is nicely saucy but not runny. Serve warm, scooping down through the browned cheese to get a mix of beef and cauliflower in every portion.
