Duck Rillettes

Preheat the oven to 250 degrees F (120 degrees C). Line a 9x13-baking dish with two pieces of aluminum foil.

Make the spice rub: Stir kosher salt, pepper, and thyme together in a small bowl. Make the seasoning mix: Mix garlic, thyme sprigs, garlic, ginger, and bay leaves together in another bowl.

Season duck all over, both inside and out, with about 2/3 of the spice rub. Fill the cavity with all of the seasoning mix. Place duck, breast-side up, into the prepared baking dish and season with remaining spice rub. Wrap duck tightly in aluminum foil.

Roast in the preheated oven until meat pulls away from the bones, 5 to 6 hours. An instant-read thermometer inserted into the center should read at least 165 degrees F (74 degrees C). Cool duck with its accumulated juices, wrapped in aluminum foil, to room temperature, about 1 hour. Chill in the refrigerator for 12 hours.

Pick meat from the bones and place into a bowl.

Spoon all accumulated juices in the foil into a saucepan and set over medium-high heat. Cook until hot throughout, about 5 minutes. Strain juices through a fine-mesh strainer into a bowl. Let fat and stock separate, then transfer fat from the top to another bowl.

Mash duck meat, 3 tablespoons duck fat, 2 tablespoons duck stock, butter, brandy, parsley, chives, Dijon mustard, cayenne pepper, salt, and black pepper together in a bowl with a wooden spoon. Transfer to to a sealable container, press down, and drizzle a little duck fat over the top. Sprinkle thyme leaves, more black pepper, and orange zest over the top. Seal the container and refrigerate for the flavors to blend, 1 to 3 days.