Prepare the pork: Pat the pork shoulder dry with paper towels. Score the skin in a crosshatch pattern with a sharp knife, being careful not to cut too deep into the meat.

Make the rub: In a bowl, mix minced garlic, fennel seeds, rosemary, salt, black pepper, red pepper flakes, olive oil, and lemon juice to form a paste.

Season the pork: Rub the spice mixture all over the pork, making sure to get it into the scored cuts and under the skin if possible. Let it marinate for at least 1 hour (or overnight for best flavor).

Preheat oven to 325°F (165°C). Place the pork on a rack in a roasting pan, skin side up. Add 1 cup of water to the bottom of the pan to prevent burning.

Roast the pork: Cook for about 3 hours, or until the internal temperature reaches 160°F (71°C). For extra crispy skin, increase oven temperature to 450°F (230°C) for the last 15 minutes.

Rest and serve: Remove from oven, tent with foil, and let rest for 20 minutes before slicing. Serve with pan juices drizzled over the top.