In a large bowl, mix together onion, beef, and spices. Divide into 4 even patties.
Heat a large skillet over medium-high heat, add olive oil. Place burgers in the pan and cook for approximately 8 minutes on each side. Remove to a plate and set aside.
Sprinkle flour over the drippings in the pan and whisk gently. Cook flour mixture an additional five minutes, stirring constantly and scraping up any bits in the bottom of the pan.
Slowly add the beef broth, whisking to dissolve any lumps. Stir milk into the mixture and return to a gentle simmer. Gravy will thicken. Taste and season as needed.
