2 pounds (approx.) cubed steak or another cut of thinly-sliced steak (such as eye of round or top sirloin)
2 tablespoons butter
3/4 cup AP flour
1 can cream of mushroom soup
1 can golden mushroom soup
3 cups whole milk
4 ounces button mushrooms, sliced
Season both sides of each piece of meat with salt and pepper. Pour the flour into a gallon-size plastic bag. Season flour liberally with salt and pepper. Seal and shake to incorporate.
Melt 1 tablespoon butter in a large, heavy-bottomed skillet set to medium-high heat. Place half (usually 4 – 5 pieces) of steak into the baggie of flour. Seal and shake to coat steak. Shake off excess flour and brown both sides of steak in the skillet. Transfer to slow cooker. Add the other 1 tablespoon of butter to the skillet. Allow to melt, then repeat the browning process with the remaining steak.
Once all steaks are browned, return skillet to stove top and add in both cans of soup. Whisk to combine, then add in milk. Whisk to incorporate and bring to a gentle simmer. Be sure to scrape up any brown bits remaining in the bottom of the pan from browning steaks. Season with salt and pepper to taste. Stir in the sliced mushrooms. Pour sauce into slow cooker to coat steaks. Be sure some of the gravy gets between each piece of meat and on the bottom of the insert.
Cover and cook on low for 7 – 8 hours. Serve over mashed potatoes or even cooked rice.