Salisbury Steak with Mushroom Gravy

1 pound lean ground beef (sirloin)
1 (10-ounce) can cream of mushroom soup, divided
1/2 cup Italian bread crumbs
1 egg, lightly beaten
1/4 cup chopped onions
1/2 teaspoon salt
1 teaspoon pepper
1/2 teaspoon minced garlic
1 tablespoon olive oil
2 tablespoons butter
1 (8-ounce) package sliced fresh mushrooms
2 cups low-sodium beef broth
1 (1.2-ounce) packet McCormick (or any brand) brown gravy mix

In a large bowl, combine beef, 1/4 can mushroom soup, bread crumbs, egg, onions, minced garlic, and seasonings. Mix thoroughly and shape into 4 oval patties. If you find that your patties are too lose and wet you can add a little more breadcrumbs …but not too much. Heat olive oil and 1 tablespoon butter in large skillet over medium-high heat. Brown patties on both sides and transfer to a plate.

Add remaining butter and saute mushrooms for 7 to 8 minutes. Add beef stock and whisk in gravy mix until smooth. Stir in remaining mushroom soup. You can add up to a 1/4 more broth for thinner gravy. Return patties to skillet and spoon gravy over top. Cover pan and simmer for 20 to 25 minutes.