Brown steak in skillet with 2T. olive oil. Transfer to crock pot and set aside. In a small bowl, combine tomato sauce, and seasonings. Place potatoes, carrots and mushrooms on top of browned steak and pour sauce over all.
Cover and cook on low for 8 hours or until steak is tender and veggies are done.
For gravy if you like it: Add 1/4 cup of beef broth and 2 T. of flour to crockpot about 30 minutes before serving allow to cook and thicken.