Slow-cooker mushroom steak and slow-cooker pepper steak are good recipes for cooking steak in a slow cooker. Both recipes can be prepped in less than 25 minutes and allowed to cook all day unattended and provide a full meal for a family of six.
For mushroom steak, open a 4-ounce can of sliced mushroom, and drain the liquid into a separate bowl. Add 3-pounds of boneless sirloin or flank steak to a 6-quart slow cooker. Top the steak with the mushrooms and 1 medium sliced onion. In the bowl with the mushroom juice, add a 10 1/2-ounce can of condensed mushroom soup, 1 cup of dry red wine and a dash of black pepper and garlic powder. Stir the mixture well, and pour it into the slow cooker. Cook on low for about 10 hours or until the beef is fork tender.
For the pepper steak slice 2 pounds of sirloin into 2-inch strips and sprinkle the strips with garlic powder to taste. Brown the meat using 3 tablespoons of vegetable oil in a large skillet and transfer to the slow cooker. Dissolve 1 beef bullion cube in 1/4 cup of hot water and stir in 1 tablespoon of corn starch, and when the mixture is fully dissolved, add it to the meat. Stir in 2 large green bell peppers roughly chopped, 1/2 cup of chopped onion, a 14 1/2-ounce can of stewed tomatoes with juice, 3 tablespoons of soy sauce and a teaspoon each of sugar and salt. Cook on low for about 8 hours and then serve.