01 -
Throw beef, breadcrumbs, egg, milk, seasonings, along with 1 tbsp each of Worcestershire sauce and ketchup into a bowl. Mash it all together and make four oval shapes.
02 -
Cook patties in a big pan over medium heat until both sides have a nice brown crust. Take them out after.
03 -
In the same pan, toss in onions, mushrooms, and butter. Keep cooking and stir up the crispy stuff stuck on the pan until it’s golden.
04 -
Sprinkle flour into the pan and mix till it looks golden. Slowly pour in broth, the rest of the ketchup, Worcestershire sauce, and mustard.
05 -
Pop the patties back into the skillet. Let them cook 10 minutes till the sauce thickens and the meat hits 165°F.