Blood Sausage, Roasted Apples, Pommes Purées, and Mustard
For the Boudin Noir:
Sweat the onion in the oil over a low heat until translucent. Cool thoroughly. In another pan, sauté the apples over high heat, stirring often, until slightly brown. Let cool. Grind the nutmeg, cumin, and coriander. In a grinder set over a small plate, grind the pork fat back, lean pork, nutmeg mixture, salt, and pepper. In a blender combine the blood, milk, and brandy. Blend until just smooth. Combine the ground pork mixture with the blood mixture and apple mixture in a stand mixer fitted with a paddle attachment and mix until just integrated.
Bring a large pot of seasoned water to a boil. Placing one end of the softened casing over the faucet of a sink, thoroughly rinse the inside of the casing. Tie off one end of the casing and feed the casing onto a funnel. Pour the sausage mixture into the casing, trying to avoid any bubbles. Once the sausage mixture is in the casings, carefully link the sausages, trying to keep the sausages evenly filled. Drop the linked sausages into the boiling, seasoned water and drop the heat to low. Poach for 30 minutes and turn off the heat, allowing the poaching water to cool to room temperature before cutting the sausages apart and refrigerating.
For the Caramelized Apples:
In a heavy-bottomed skillet, heat the clarified butter over medium high heat. Sauté the apple slices on both cut sides until golden. Remove apple slices from the pan and reserve. Add honey to the pan and cook for no more than 30 seconds. Add the wine, salt, and pepper and reduce to a thin caramel consistency. Swirl in the butter and sautéed apple slices. Cook until glazed, about 2 to 3 minutes.
For the Pommes Purées:
Starting with cold water, boil the potatoes until fork-tender, about 30 minutes. Run the potatoes through a ricer into a pot and stir over very low heat until steam no longer escapes, about 5 minutes. Vigorously stir the butter into the potatoes until incorporated. Add ¾ cream of the milk in a slow stream while vigorously whipping the potatoes, incorporating air into the mixture. Season with salt and pepper and add more cream as necessary.
To Assemble and Serve:
Preheat the oven to 350°F. In a sauté pan, crisp the Boudin Noir over medium heat on both sides and put in the oven until warmed through. Plate the Boudin Noir, Caramelized Apples, and Pommes Purées. Serve with a side of the whole grain mustard.