I can't remember where this family tradition first came from, and to be truthful, I now really don't care. All I know is every time we have a family barbecue, this tasty little delight is on the menu.
The house that I grew up in had a pleasant abundance of citrus. Lemon, orange, lime and kumquat. Apart from the fruit, we had delightfully scented leaves left over.
What makes this snack so special is the simple act of picking the citrus leaves, topping with cheese and grilling on the barbecue, while everyone chews the fat and waits for the main meal. The leaves impart a delicate and haunting citrus flavour to the cheese and the whole affair is served up not on plates, but the leaves themselves. Just eat the cheese off the leaf.
What we mostly use is bocconcini cheese, but the thing you must remember is that the cheese is interchangeable. The citrus leaf is providing the flavour and enchantment, so feel free to substitute. What you want is any cooking cheese wish a high moisture content, to sap up the citrus flavour. Try mozzarella, gruyere, tilsit, asiago, pecorino fresco or haloumi.
Make sure you have a decent BBQ going. Don't go to the trouble just for this dish and don't try making it without real fire either.
Pick the citrus leaves and wash. Cut slices of cheese to match the leaves, top and place over the hot coals, leaf side down. Cook for 1-2 minutes, or until the cheese is bubbling and delightful smells are in the air. Eat immediately.