General tips
Roll porchetta tight around the herb crust. Air gaps mean dry pockets and uneven cooking. Use butcher's twine and tie every two inches along the length. The roll should feel firm and uniform, like a sausage. Loose rolls fall apart in the bath.
Cook at 145°–150°F for 12–18 h. Lower temps don't fully break down the connective tissue between the belly and the loin; higher temps dry out the loin. The sweet spot is 145°F for sliceable, juicy porchetta with rendered (but not melted-away) fat.
Score the skin in a tight crosshatch before bagging. The scoring lets fat render and creates those iconic crispy squares when you blast the porchetta in a hot oven at the end. Don't cut into the meat - just through the skin and the first layer of fat.
Finish at 475°F oven for 20 min to blister the skin to glass. The bath cooks the meat through; the high-heat oven turns the skin into shattering crackling. If the skin doesn't blister, your skin wasn't dry enough - uncover the porchetta in the fridge overnight before bagging next time.
Anti-tip: don't slice porchetta thin. The classic Italian way is thick slices, almost like steak, that let you taste the herbed pork against the crackling skin. Thin slices lose the textural contrast that makes the dish work. Cut bold, eat well.
Tender & Juicy tips
Score skin for extra crispy crackling
Fennel seeds are traditional and essential
Let rest before slicing for juicy meat