Sauté mushrooms in butter if using fresh, until tender. If using canned, drain well. Either way, cook or not, set aside
In a large skillet, heat oil
Salt steaks and dredge in flour
Fry steaks until brown (be sure to leave the meat in long enough for the breading to fry until it sets or it will fall off if not fried long enough)
Once the steak is fried, remove from pan and place on paper towel to drain excess oil - keep warm
Leave 2 TBS of oil in pan and remove the rest.
Add cream of mushroom soup, milk and mushrooms, stiring constantly
Let simmer on medium/low until heated thoroughly
Pour over warm steak and serve.