Last one I did, I went the Mediterranean style. I marinated it, skin side up, in olive oil, garlic, herbs, (or you could go porchetta spices) and a bit of soy sauce. Score the skin every 1/4 inch, keep it very dry, and spread a bit of rock salt over it. A dry skin at all times is important to achieve a nice crisp crackling. Let this sit over night and then wipe off the salt and slow roast the next day for a couple of hours. Then crank up the heat at the end to get the crackling nice and crispy. Let it sit for 10 15 minutes before slicing. I had mine with a saucy potato, and veggies.....