Heat a large skillet over medium-high heat, once hot add olive oil.
Dredge the cube steak through flour and add to the hot oil, cook until skin is golden in color, about 5 minutes (Cook in batches and don’t overcrowd your pan)
Add half of onion slices and mushroom slices in the bottom of the crockpot, and then add the fried cube steaks on top. Add the rest of onion and mushroom on top of the steaks.
In a medium-sized bowl whisk together cream of mushroom soup, onion soup mix, gravy packet, beef stock and thyme, add to slow cooker
Cover and cook 2 to 4 hours on high setting or 4 to 6 hours on low setting, until the steak is cooked through and tender
Transfer the steak and vegetables to serving plates
If the sauce is not thick enough, mix 1 tablespoon cornstarch and 1 tablespoon water and pour into the sauce. Cook 10 to 15 minutes to thicken the sauce into gravy.
Serve with mashed potatoes and broccoli
Notes
If you like a smoother gravy, you can pour the sauce through a strainer before adding the cornstarch and water mixture.