When talk turns to Hawaii, people usually mention the American state's beaches, beautiful scenery, fantastic weather and surfing.

I automatically think of its onions.

Our neighbours back in California were from Hawaii, and every summer they'd go "back home" to visit relatives. On their return, they'd give us gifts of Portuguese sweet bread (which is very good), chocolate-covered macadamia nuts (which is a waste of a delicious nut), potato chips (fantastic) and Maui onions that were so sweet and delicious you could eat them like fruit. These so-called "sweet onions" grow in other parts of the world, including Vidalia (in Georgia - the one in the United States), Walla Walla (in Washington state) and Cevennes (in France). The onions are usually named after the place where they're grown.

You'd probably be hard-pressed to tell sweet onions apart from regular onions just by looking at them, but the flavours are completely different. Rather than being pungent and strong, with sulphur compounds that make your eyes water when you cut into them, these onions are sweet and mild. While regular onions need to be slowly braised to bring out their sweetness, the flavour of sweet onions is best appreciated when they're raw or cooked just briefly.

One of the simplest ways to enjoy sweet onion is to put it in a sandwich. Spread home-made mayonnaise on good-quality bread, lay slices (about 5mm thick) of sweet onion on the bread, sprinkle with a little salt and a good amount of black pepper, then cover with another layer of bread. Sweet onions also make a delicious addition to the classic BLT.

For sweet onion rings, cut the onions about 8mm thick then separate the slices into rings. Dip the pieces into a light tempura batter, then quickly fry them in hot oil (180 degrees Celsius). Drain on paper towels, sprinkle lightly with sea salt and serve immediately.