Mondeghili (fried breaded beef and pork meatballs)

Ingredients

• 50g unsalted butter
• 25g onion, finely chopped
• 25g celery, finely chopped
• 25g carrot, finely chopped
• 500g cooked beef, finely chopped
• 75g mortadella, finely chopped
• 75g stale bread, whizzed into crumbs
• 50ml red wine
• 125ml whole milk
• 125g grana padano, finely grated
• 2 medium eggs
• 2 rosemary sprigs, leaves picked and finely chopped
• 4 thyme sprigs, leaves picked and finely chopped
• 2 sage sprigs, leaves picked and finely chopped
• 30g plain flour
• 1 medium egg, beaten
• 40g fine breadcrumbs
• Olive oil to fry