• Place the kidney beans in a bowl, cover with water, and soak overnight at room temperature. The next day, drain well.
• Preheat the oven to 350°F (180°C).
• In a large pot, melt 1⁄4 cup (60 mL) of the butter over medium heat. Add the boar bacon and cook for 3 minutes. Add the onion, carrot, celery, and garlic, stir to combine, and cook for another 2 minutes. Add the drained kidney beans, white wine, 4 cups (1 L) of the game stock, 1 teaspoons (5 mL) of the salt, 1 teaspoon (5 mL) of the pepper, thyme, bay leaves, and the confit goose legs. Bring to a simmer.
• Cover with a lid, transfer to the oven, and cook for 11⁄2 to 2 hours, stirring occasionally and checking to see if the stock has all been absorbed, topping up with more stock as necessary. The beans should be plump and tender, with some liquid in the pot but it shouldn’t be soupy. Discard the bay leaves and thyme stems before serving.
• Reduce the oven temperature to 325°F (160°C).
• Season the goose breasts with the remaining 1 teaspoon (5 mL) salt and 1 teaspoon (5 mL) pepper. In a large skillet, heat the grapeseed oil and the remaining 1 tablespoon (15 mL) butter over medium-high heat.
• Add the goose breasts skin side down and sear, turning once, until brown on both sides. Transfer to the oven and cook for 5 to 10 minutes, to an internal temperature of 125°F (50°C) for medium-rare or 135°F (57°C) for medium doneness. Let the meat rest for 5 to 8 minutes before serving.
• Thinly slice the breast meat and serve on top of the cassoulet.

Make the Sausage Gravy

• Break up the sausage meat in a medium skillet over medium-high heat and cook until brown, 2 to 3 minutes. Add the salt, then sprinkle the flour over the sausage to soak up the fat. Stir with a wooden spoon, making sure there are no lumps of flour. Stir in the milk, reduce the heat to low, and simmer until the gravy is thick, 3 to 4 minutes. Remove from the heat and keep warm.