01 - In a shallow dish, whisk together the all-purpose flour, kosher salt, black pepper, smoked paprika, and garlic powder until evenly combined.
02 - Coat each cube steak thoroughly in the seasoned flour mixture, pressing gently to adhere. Shake off any excess and reserve the leftover seasoned flour for the gravy.
03 - Heat 2 tablespoons of vegetable oil in a large skillet over medium-high heat. Working in batches to avoid crowding, sear the dredged cube steaks for 2 to 3 minutes per side until deeply golden brown. Transfer the browned steaks to a plate and set aside.
04 - Reduce heat to medium and add the remaining 1 tablespoon of vegetable oil to the skillet. Add the thinly sliced onion and cook for 5 to 6 minutes, stirring occasionally, until softened and lightly caramelized. Stir in the minced garlic and cook for 1 additional minute until fragrant.
05 - Sprinkle 2 to 3 tablespoons of the reserved seasoned flour over the onions and stir continuously for 1 minute to cook out the raw flour taste.
06 - Slowly pour in the beef broth and whole milk while whisking constantly, scraping up all the browned bits from the bottom of the skillet. Stir in the Worcestershire sauce and dried thyme. Bring to a gentle simmer and cook for 3 to 5 minutes until the gravy begins to thicken slightly.
07 - Nestle the browned cube steaks and any accumulated juices back into the skillet, submerging them in the gravy. Cover with a tight-fitting lid, reduce heat to low, and simmer for 25 to 30 minutes until the steaks are fork-tender and the gravy is rich and velvety.
08 - Taste the gravy and adjust the seasoning with salt and pepper as needed. Garnish with freshly chopped parsley and serve hot over mashed potatoes, steamed rice, or buttered egg noodles.