Bone Marrow Flan With Steak

Ingredients

8 2-inch beef marrow bones, both ends cut to expose the marrow (the bones should be smooth and cylindrical for the most attractive appearance)
½ cup minced shallots
1 cup dry red wine
¾ cup heavy cream
2 large eggs
Salt and freshly ground black pepper
1 ½ cups milk
8 10-12 ounce boneless sirloin strip steaks
Kosher salt

8 servings

Preparation

Chill the marrow bones at least one hour. Using a long thin knife, cut around the inside surface of the bone, and push out the marrow in one piece. Place the marrow in a bowl of cold water, and refrigerate at least 3 hours, up to 24 hours.
While the marrow is refrigerated, place the empty bones in a pot and cover with water. Simmer until all the fat and meat can easily be scraped away, about 2 hours. Remove the bones from the water, scrape them clean, and set aside.
To prepare the flan: In a small nonreactive saucepan, combine the shallots and wine. Bring to a simmer, and cook until almost all the wine has evaporated, about 30 minutes. Remove from the heat and allow to cool. In the container of a blender or food processor, combine the cream, eggs, and shallot mixture. Puree until smooth. Season to taste with salt and pepper. Strain through a fine strainer, and set aside.
Preheat oven to 300 degrees. Place teakettle of water over high heat to bring to a boil. Wrap the bottom half of each bone tightly, first with plastic wrap, then with foil. Stand each bone up in a deep roasting pan with the foil on the bottom. Pour the flan mixture into each bone, filling them up halfway. Cover the pan with a lid or heavy-duty foil, and place in the oven. Bake for 45 minutes. Remove from the oven but keep in the pan.
Prepare a hot grill or broiler. Remove the marrow from the ice water, and cut into slices 1/2 inch thick. Grill or broil the steaks to taste. While the steaks are cooking, place the milk in a small skillet over low heat and bring to a slow simmer. Add the marrow slices, and poach until the surfaces are smooth and they are heated through, about 5 minutes.
To serve, place each steak on a plate. Carefully remove the foil and plastic from each bone, and place a bone, flan side down, on each plate. Fill the empty top halves of each bone with the poached marrow slices. Serve immediately.