Pot-roast loin of pork with celeriac, shallots & pancetta

INGREDIENTS

• about 2½kg British pork loin
• 6-8 garlic cloves , peeled and cut into thin slivers
• 7 tbsp olive oil
• 1 lemon , juice only
• 1 tsp dried fennel seeds
• 8 sprigs fresh oregano
• 300g shallots
• 1 large celeriac , quartered and peeled
• 1 x 130g twin-pack cubetti di pancetta (small cubes of Italian cured belly pork)
• 600ml full-bodied red wine - drink the remainder!