Step 1: 1. Simply cut the buns in half/open and spread with ketchup, sprinkling the 3 grated cheeses on top (at this point you can sprinkle on a little mixed herb or a dab of sour cream and chive sauce if you like).
Step 3: 2. Place in a pre-heated grill at a medium temp. till the cheese is melted and bubbling
Step 5: 3. Sprinkle a little salt to taste and get munching!