Step 2: Make the Gravy
1. In the same skillet, melt the butter over medium heat.
2. Add the sliced onion and sauté until softened, about 3-4 minutes.
3. Sprinkle the flour over the onions and stir to form a roux. Cook for 1–2 minutes to eliminate the raw flour taste.
4. Slowly whisk in the beef broth and heavy cream, stirring constantly until the sauce thickens, about 5-7 minutes.
5. Add Worcestershire sauce, salt, and pepper to taste.
Step 3: Assemble the Dish
1. In a baking dish, arrange the cooked hamburger patties.
2. Pour the prepared gravy over the patties, making sure they are generously covered.
3. Cover the baking dish with aluminum foil and bake for 25-30 minutes, until the patties are heated through and the flavors have melded together
