Crispy Prosciutto and Provolone Burgers | D'Italiano

Ingredients

• 4 D’Italiano® Original Crustini Buns
• Red onion 1 small , tough outer layers peeled and discarded
• 400 g ground beef
• 1 tsp. celery salt
• Flat-leaf parsley a handful, finely chopped
• 4 slices of prosciutto
• Oil for frying
• 4 slices of provolone (or fontina)
• Lettuce leaves to serve
• 4 tbsp. mayonnaise
• 3 tsp. sweet mustard
• 6 cornichons , chopped
• 4 pickled onions , chopped