Prepare all ingredients by measuring spices, chopping vegetables, and having everything within reach.
Combine all ingredients for the patties in a bowl and form into four oval-shaped patties.
Heat olive oil in a skillet and brown the patties for about 5–6 minutes on each side.
Sauté onions and mushrooms in the same skillet until seared and moisture has evaporated.
Make the gravy base by melting butter and sprinkling in flour, stirring constantly.
Whisk in beef broth gradually until smooth.
Add Worcestershire sauce and garlic powder to the gravy, adjusting seasoning as needed.
Combine the sautéed onions and mushrooms with the patties in the gravy and simmer for 5–7 minutes.