This seems like a fiddle but it's not and it tastes fantastic.
4lb pork loin
1 large onion chopped
2tbsps fennel seeds
3 cloves crushed garlic
1/2 tsp ground cloves
2 sprigs fresh rosemary finely chopped
4-5 bay leaves findely chopped
Get your pork loin and split/cut in half lengthways (not all the way through). Cover in Gladwrap and bash with a rolling pin until it's about 1in thick.
Fry the onion in 2 tbsps olive oil and when softened add the garlic, rosemary, bay leaves, fennel seeds, ground cloves for a minute or so. Add a good amount of salt and pepper. Then put on a plate to cool.
Spread the onion/herb/spice mixture on the pork and roll up, then tie with string (you may need someone to help you with this bit). Drizzle with more olive oil, cover losely with Gladwrap and leave in the fridge overnight or 24 hours.
Take the pork out of the fridge and let it get to room temp (about 45 mins) before putting in a moderate oven, 180C, for 4 hours. Check after 3 hours and if it's getting too blackened turn the temp down a bit.
Take out of oven and allow to rest for 20 mins before serving. Delicious with roast potatoes and steamed veggies, or do like the Italians do and serve shredded in ciabatta rolls or other fresh bread. Peasant food at its best.