Hamburger Steak with Onion & Mushroom Gravy

Hamburger Steak with Onion & Mushroom GravyRecipe adapted from Cooking Light
Ingredients:
2-3 teaspoons extra-virgin olive oil
1 teaspoon butter
1 pound ground sirloin
kosher salt and freshly ground pepper
1 large white onion, vertically sliced (about 1 1/2 cups)
1 cup sliced mushrooms (like baby portobellos)
4-5 cloves garlic
1 tablespoon all-purpose flour
1 1/2 cups low-sodium beef stock
1 teaspoon red wine vinegar
Mashed potatoes (make ‘em with roasted garlic and buttermilk for extra deliciousness)
Instructions:
Divide the meat into 4 1/2″-thick patties. Season both sides with salt and pepper. Set aside.
Swirl 2 teaspoons in olive oil in a large non-stick skillet over medium heat. When the oil is hot, add the patties and cook for 4-5 minutes and then flip and cook for another 4-5 minutes or until cooked through. Remove the patties from the pan and set aside.
Heat the teaspoon of butter in the skillet. When melted, add the onions and sprinkle lightly with salt and freshly ground pepper. Cook, stirring frequently, until they become tender and start to caramelize, about 5-7 minutes (you may need to add an additional teaspoon of oil if the onions are burning or sticking). Add the mushrooms and garlic and cook until the mushrooms are tender, being careful not to let the garlic scorch.
When the onions and mushrooms are cooked, sprinkle them with 1 tablespoon of flour and stir quickly to combine. Add the broth and vinegar and cook until thickened. Add the beef patties and heat through. Serve each patty over mashed potatoes and top with mushrooms, onions, and gravy. Serves 4.

 Original recipe found HERE