Pour this 1 rich mixture over seared beef patties into a cast iron skillet for a hearty dinner that feels like real comfort food

With the onions and mushrooms still in the skillet, carefully pour this one rich mixture of beef broth, sliced onions, mushrooms, and brown gravy mix over them, scraping the bottom of the pan with a wooden spoon to release any browned bits. Bring the mixture up to a gentle simmer over medium heat; it will start to thicken slightly.
Nestle the seared beef patties back into the cast iron skillet, right into the simmering gravy. Spoon some of the onion-mushroom mixture over the top of each patty so they’re nicely coated.
Reduce the heat to medium-low, cover the skillet with a lid (or tightly with foil if you don’t have a lid), and let everything simmer together for 10–15 minutes. The patties should cook through to an internal temperature of 160°F, and the gravy will thicken and become rich and glossy.
If you’d like the gravy a bit richer, stir in the butter at the very end until melted and fully incorporated. If the gravy seems too thick, add a splash of beef broth or water to loosen it; if it’s too thin, let it simmer uncovered for a few more minutes.
Taste the gravy and adjust the seasoning with a pinch more salt and pepper if needed. Serve the Salisbury steaks hot, spooning plenty of the onion-mushroom gravy over each patty. Garnish with chopped fresh parsley if you like, and enjoy right from the cast iron skillet at the table for that cozy, family-style feel.
Variations & Tips
For picky eaters who don’t love mushrooms or onions, you can slice them very thin so they almost melt into the gravy, or cook them separately and only pour the smooth part of the gravy over the kids’ portions. You can also skip the mushrooms entirely and double the onions for a simpler onion gravy. If you’re trying to lighten things up a bit, use leaner ground beef or a mix of ground beef and ground turkey; just be careful not to overcook, since lean meat dries out faster. For a gluten-free version, use gluten-free breadcrumbs in the patties and choose a gluten-free brown gravy mix. To stretch the meal for a bigger family, shape the meat into 6 smaller patties instead of 4 and add an extra 1/2 cup of beef broth plus a few more mushrooms to keep the gravy plentiful. If you like a deeper Southern-style flavor, add a splash more Worcestershire sauce to the gravy or a pinch of smoked paprika to the meat mixture. Leftovers reheat nicely in a skillet over low heat with a splash of broth to loosen the gravy, and they make an easy next-day lunch over toast or rice.