Preheat the oven to 400 degrees F.
In a bowl, blend the ground beef, onions, garlic, salt and pepper and mix well.
Next, by hand, portion the meat into 8 to 9 round patties, ensuring they are not more than 1/4-inch tall. Next, heat a large saucepan with the oil over medium-high heat. Add the seasoned patties, allowing to cook on each side until browned, 3 to 4 minutes. After browning both sides, finish in the oven for 4 to 5 minutes for medium-well. Remove from the oven.
After baking, remove the patties from the pan and hold on the counter; this will allow the meat to rest. Then, return the pan to medium-high heat for 2 minutes. After the pan is hot again, carefully add the brandy and allow the liquor to cook off. Then add the stock, mushrooms, herbs and nutmeg and cook for 3 to 4 minutes, allowing the sauce to reduce to 1 cup volume. After reducing the sauce, remove the pan from the heat and whisk in the butter to finish the sauce. Serve with the chopped steak.
Recipe courtesy of Robert Irvine