In a large bowl, combine ground beef, breadcrumbs, egg, milk, Worcestershire sauce, Dijon mustard, garlic, salt, pepper, smoked paprika, and grated onion. Mix gently with your hands until just combined. Do not overmix—it can make the patties tough.

Divide the mixture into 4 equal portions and shape them into oval patties. Press slightly in the center so they cook evenly.

Heat a skillet over medium-high heat and add a little oil. Place the patties in the pan and sear for about 4–5 minutes on each side until browned. Remove and set aside.

In the same pan, add butter and olive oil. Toss in the sliced onions and cook slowly over medium heat. Stir often until they become soft and golden brown. This step builds deep flavor, so don’t rush it.

Add garlic to the onions and cook for about 30 seconds. Sprinkle in the flour and stir well to coat the onions. Slowly pour in the beef broth while whisking to avoid lumps.

Add Worcestershire sauce and thyme. Let the gravy simmer until it thickens slightly.

Return the patties to the pan, nestling them into the gravy. Cover and simmer for 10–15 minutes until the patties are fully cooked and tender.

Serve hot with mashed potatoes, rice, or even crusty bread to soak up that rich gravy.