Preheat oven to 325℉

Stir together flour and seasoned salt on a large plate. Dredge both sides of each cube steak in flour mixture, shaking off excess. Save the unused flour for thickening gravy.

Heat half of the vegetable oil in a Dutch oven over medium-high heat. When the oil is hot add 3 steaks and cook until golden brown, about two minutes on each side. Remove steaks to a plate and set aside. Add remaining vegetable oil and repeat to brown the remaining 3 steaks. Remove steaks to a plate and set aside.

With the heat still on medium-high, add the butter, onion, and mushrooms. Cook, stirring frequently until mushrooms have browned, about 3-5 minutes.

Add the excess flour to the pan. Coat the mushrooms and onions with flour.

Slowly add the beef broth to the pan while whisking to prevent clumps of flour. Continue to add the chicken broth, and worcestershire sauce to the pan while whisking. Bring to a boil while using whisk to scrape the bottom of the pan to remove and incorporate all of the browned bits.

Reduce heat and simmer for 5 minutes. Add the steaks to the gravy, nestling them into the sauce as much as possible.

Cover Dutch oven and place in preheated oven. Cook for 1 ½ hours.