Marinate the Boar: Cut wild boar meat into pieces and place in a container. Add chopped celery, carrot, garlic, parsley, sage, rosemary, bay leaves, juniper, and peppercorns. Cover with red wine and let it marinate for at least 6 hours at room temperature, overnight is better.
Prepare the Soffritto: In a casserole, sauté a coarse mix of celery, carrot, and onion in olive oil. Add cubed guanciale and cook on low heat for a few minutes.
Cook the Boar: Remove the meat from the marinade, pat dry, and cut into small pieces, almost like ground meat. Add to the pan and cook over medium heat. Add juniper berries, bay leaves, a pinch of salt, and blended peeled tomatoes. Simmer on low heat for about 1 hour and 30 minutes, adding hot water as needed to keep it moist.
Combine with Pappardelle: Cook pappardelle according to package instructions. Mix the pasta with the prepared ragù.
Serve: Plate the pappardelle with ragù and enjoy a taste of Florence!