In a large bowl combine all the hamburger steak ingredients together well. Shape into 6 patties. Dip each into flour, coating well on all sides.
Over medium-high, heat the olive oil in a large skillet. Fry burgers until golden brown. Remove from skillet and set aside, reserving all the pan drippings for the gravy.
In the skillet with the drippings, over medium heat, add the sliced onions and stir to coat well. Add sliced mushrooms. Cook, stirring frequently, until lightly caramelized, about 20-30 minutes.
While onions and mushrooms are cooking, in a medium bowl whisk together the rest of the gravy ingredients.
Pour the liquid gravy mixture into the skillet with the caramelized onions and mushrooms. Stirring constantly, heat over medium until mixture begins to thicken.
Return the hamburger steaks to the skillet, flipping a few times to coat with the gravy. Cover and reduce heat to simmer. Cook covered for 20 minutes, flipping every 5 minutes to keep well coated.
Serve with your favorite potatoes recipe, or noodles, or rice.
