- Season beef with salt on all sides. Place coarse pepper in a shallow dish and dip the cut sides of the filets into the pepper, pressing lightly to coat.
- Heat 1 tablespoon of butter in a large saute pan or skillet over medium-high heat. Add the steaks and sear on both sides until well browned, 2 minutes on each side. Transfer the steaks to an oven-proof baking dish and place in the oven. Cook for 8 to 10 minutes for medium-rare.
- While the steaks are cooking in the oven, add 1 tablespoon of the remaining butter to the same saute pan used for the steaks. Add the mushrooms and cook over high heat, stirring frequently, until golden brown around the edges, 2 to 3 minutes. Remove the mushrooms from the skillet and reserve.
- Remove the skillet from the heat and add the garlic cloves and 6 tablespoons of the brandy to the hot pan, stirring to loosen any browned particles from the bottom of the pan. Return the skillet to the heat, being careful that the brandy does not flame up. Cook until reduced by half; this will happen very quickly.
- Add 2 tablespoons of the remaining butter and the brown sugar, stirring to combine.
- When the sugar has dissolved and the mixture is bubbly, whisk in the cream, reduce the heat to medium-high and simmer for 2 to 3 minutes, until mixture is sauce consistency and coats the back of a spoon.
- Add the reserved mushrooms to the pan and season with the salt, and pepper.
- Remove from the heat and whisk in the remaining tablespoon of butter and the remaining tablespoon of brandy. Serve immediately over warm steaks.