In a skillet, place about 2 Tablespoons of olive oil, heat and add mushrooms. For about 5-10 minutes, saute them evenly. Remove them from pan, set aside. Remove any liquid from the pan.
In a bowl combine your ground beef with all of the meat ingredients, and form into 6 oval shaped patties. Place a couple of Tablespoons of butter in your skillet, and add meat, brown over medium heat, flipping them to brown evenly on both sides. Once they are browned evenly, remove them from the pan and set them aside.
Add onions to the pan, and saute them along with the garlic until they are fragrant and translucent. Add olive oil to the pan if needed.
Add in the Worcestershire sauce, ketchup. kitchen bouquet and broth. Add mushrooms back in. Bring to a boil and then reduce heat to low. Add cornstarch mixture and whisk incorporate. Gravy will begin to thicken.
Add meat back into the pan, and simmer covered for about 30 minutes. turn meat every 10 minutes or so, and give the gravy a a stir. Take care as to not break the patties. Salt and Pepper to taste.
Serve over mashed potatoes.
