01 -
In a large bowl, gently mix ground beef, breadcrumbs, beaten egg, diced onion, salt, and black pepper until just combined.
02 -
Form the mixture into 6 to 8 oval-shaped patties and allow them to rest while preparing the gravy.
03 -
In an oven-safe skillet, brown patties over medium-high heat for 3 to 4 minutes per side until deeply golden, then remove and set aside.
04 -
In the same skillet, melt butter and sauté sliced onions until fragrant. Add flour and cook, stirring constantly for 2 minutes, then whisk in beef broth and heavy cream until smooth.
05 -
Nestle browned patties into the creamy onion gravy. Cover skillet tightly and bake in a preheated oven at 350°F for 45 minutes. Uncover and bake for an additional 15 minutes to finish.