This has to be one of the strangest looking fruits that you can buy at the supermarket. It's also one of the most useless when it comes to conventional usage — this member of the citrus family has no pulp or juices; it's all skin and pith. But while you wouldn't squeeze this one over veggies or in your afternoon tea, its rind is a complement to almost anything and can be seen on many a fancy restaurant's menu.
Buddha's Hand hails from India and parts of China. It may have gotten its name from the way it looks like human fingers, or because it's sometimes used as an offering at Buddhist temples. In parts of Asia, it's used to decorate tabletops and as a natural air freshener. Here in the US, you may have experienced it as flavored vodka.
Instructables.com has a quick and easy recipe for candied Buddha's Hand. Here are the basics:
Chop up 1 Buddha's Hand into small strips or cubes. Put them in a pot with 3 cups of water and 3 cups of sugar, and bring to a boil on medium heat. Once it boils, simmer for 45 minutes. Once it becomes candied and syrupy, turn off the heat and let it cool for about a half hour.

I should mention that this fruit is not in season right now; you might be able to find it at the supermarket now, but you'll likely have to wait until fall, which is when it's most ready to eat