Stir together all burger ingredients. Shape into four thick patties.
Spray a skillet with cooking spray over medium-high heat. Cook burgers approximately 7 minutes per side or until cooked through. Remove from pan and set aside.
In same pan over same heat, add oil and flour. Whisk together, and cook, stirring constantly about 2-3 minutes until light brown. Slowly whisk in broth, scraping up browned bits from the pan as you go. Whisk constantly and add broth a little at a time until smooth.
Stir milk and salt and pepper into the gravy, and bring to a simmer. Pour gravy through a mesh strainer into a serving dish to remove the large pieces of onion and pan scrapings. Serve burgers smothered in gravy.
- Prep Time: 10
- Cook Time: 25