Prepare the Salisbury Steaks. Grate the onion on a box grater and add to a large mixing bowl. You can use a food processor to achieve a fine mince. Mince the garlic and add that along with the breadcrumbs. Add the ground beef, egg, ketchup, crumbled bouillon cube, Worcestershire sauce, and Dijon mustard.

Mix by hand to combine the meat mixture until well incorporated. This helps make sure that the patties will stay together. Divide the ground beef mixture and form into 10 patties.

In a large skillet add olive oil or butter and sear the ground beef steaks in batches of 4 or 5 approximately 1-2 minutes on each side. Remove to a plate. Note: they will not be cooked on the inside at this point. They will finish cooking in the mushroom gravy.

Mushroom Gravy. Add the onions and cook for 4-5 minutes until they are translucent and starting to caramelize then add the mushrooms and cook for another 2-3 minutes.

Add the butter to the skillet and once melted, add the flour, and stir to incorporate and cook for 30 seconds. This helps the raw taste of the flour cook out and the butter and flour combination will make a roux to thicken the gravy.

Using a whisk to incorporate the ingredients, add the beef stock and water. You can use water and beef bouillon cubes if you don’t have any stock. Once this is well combined with the roux, add the rest of the ingredients, Dijon mustard, Worcestershire sauce, salt, and pepper.

Add the ground beef patties back in the pan along with the juices and nestle in the gravy. Cook for 6-7 minutes on medium heat until the gravy is thickened, and the patties are cooked through. If the gravy gets a bit too thick, add a little water.

Serve with your favorite sides.