Preheat oven to 170C
Rub pork belly with a little oil, salt and pepper, adding more salt to skin as it helps it to crisp up
Add sage, rosemary and smashed garlic cloves into baking tray, even squashing some garlic cloves into slits on the belly
Roast for 2 ½ hours at 170C, then change oven settings to grill and cook the pork for a further 5-10 minutes, adding further crispiness to the skin
Remove from oven and rest for about 20 minutes then serve.