01 - Combine the flour, salt, pepper, and paprika in a shallow dish. Dredge each cube steak through the seasoned flour, coating both sides evenly, and shake off any excess.
02 - Heat the vegetable oil and 1 tablespoon of butter in a large skillet over medium-high heat. Working in batches if needed, sear the coated steaks for 2 to 3 minutes per side until a deep golden-brown crust forms. Transfer the steaks to a plate and set aside.
03 - In the same skillet, add the remaining tablespoon of butter. Sauté the sliced onions for about 5 minutes until softened and translucent, then add the mushrooms and cook for an additional 3 minutes until lightly caramelized.
04 - Pour in the beef broth and Worcestershire sauce, using a wooden spoon to scrape up any browned bits from the bottom of the pan. Bring the liquid to a gentle simmer.
05 - Nestle the seared cube steaks back into the skillet, submerging them in the onion and mushroom mixture. Reduce the heat to low, cover with a lid, and simmer for 30 to 35 minutes until the beef is fork-tender.
06 - If using, stir in the heavy cream during the final 5 minutes of cooking for a smoother, richer gravy. Taste and adjust the seasoning with salt and pepper as needed.
07 - Serve the steaks hot, spooning the onion-mushroom gravy generously over the top. Pair with creamy mashed potatoes, steamed rice, or buttered egg noodles.