1. Clean the duck, remove any visible fat. Set aside the liver and gizzard. Cut and set aside the wings, legs, feet, and neck, then carefully remove the breasts from the carcass. Cut the carcass into 4 pieces.
2. Cut the bacon slices into 1/2-inch pieces. Cook the bacon in a large pot until it’s slightly crispy, over low heat. Remove excess fat. Add the onion, wings, legs, feet, neck, and duck carcass to the pot. Brown over medium heat for about 15 minutes. Add the bay leaves, peppercorns, and 3/4 cup of water. Bring to a slow boil, skimming carefully, then reduce the heat and simmer for 3 hours.
3. Strain the broth into a glass bowl and discard the solids. Refrigerate overnight, if possible, to remove the fat that rises to the surface.
4. Heat a saucepan over medium heat. Season the duck breasts with salt and pepper, and place them, skin side down, in the saucepan. Brown for about 4 minutes, then flip the breasts and cook for 2 to 3 minutes. Transfer the breasts to a plate and let them cool enough to handle, then carefully remove the skin.
5. In a small saucepan, melt 1 tablespoon of butter over medium heat. Cook the duck liver and gizzard until fully cooked. Season with salt and pepper. Set aside.
6. Melt 3 tablespoons of butter in a thick-bottomed pot over medium heat. Cook the leeks until tender, about 5 minutes. Add the rice and stir to coat, about 2 minutes.
7. Bring 5 cups of duck broth to a gentle boil in another saucepan. Add the hot broth to the rice, 1/2 cup at a time, stirring constantly with a wooden spoon, waiting for the liquid to be absorbed before adding more. This will take about 20 minutes for the rice to absorb all the broth and be tender. At this point, the risotto should be creamy, not watery.
8. Slice the duck breasts into thin slices; slice the liver and gizzard into small pieces.
9. Season the risotto with salt and pepper; add the parsley, then add the duck breasts, liver, and gizzard in the last minute. Divide the risotto into 8 hot bowls and serve with grated parmesan.