01 - In a shallow dish, combine the flour, salt, black pepper, and paprika. Dredge each cube steak through the seasoned flour mixture, coating both sides evenly and shaking off any excess. Reserve 2 tablespoons of the seasoned flour for thickening the gravy later.
02 - Heat the vegetable oil and 1 tablespoon of butter in a large skillet over medium-high heat. Once the butter is melted and foaming, add the dredged cube steaks in batches if necessary. Brown for 2 to 3 minutes per side until a golden crust forms. Transfer the seared steaks to a plate and set aside.
03 - Reduce the heat to medium. Add the remaining tablespoon of butter to the skillet along with the thinly sliced onions and sliced mushrooms. Cook, stirring occasionally, for 6 to 8 minutes until the onions are soft and translucent and the mushrooms are deeply browned.
04 - Add the minced garlic and the reserved seasoned flour to the skillet. Stir continuously for about 1 minute to cook off the raw garlic and flour taste, allowing the mixture to form a light roux with the vegetables.
05 - Slowly pour in the beef broth and Worcestershire sauce, stirring constantly and scraping up any browned bits from the bottom of the skillet. Stir in the milk and bring the mixture to a gentle simmer, allowing it to begin thickening slightly.
06 - Return the browned cube steaks to the skillet, nestling them down into the gravy so they are partially submerged. Cover the skillet with a lid, reduce the heat to low, and simmer for 20 minutes until the steaks are fork-tender and the gravy has thickened to a rich, coating consistency.
07 - Taste the gravy and adjust the seasoning with additional salt and pepper if needed. Transfer the steaks to serving plates, spoon the onion and mushroom gravy generously over the top, and garnish with chopped fresh parsley.