If you should ever find yourself in a situation where you need a candle or two, such as a power outage, and can't find one, you're not entirely out of luck. According to reddit user KelsKaos__, all you need are some common kitchen ingredients.
Here's how it's done.
What you will need
We recommend you use an orange for this, but any citrus should work. The most important thing is that there should be no holes in at least one half of the peel.
You'll also need some olive oil. Other oils could work, but olive oil is fairly stable. It's commonly used in for candles and oil lamps as an alternative to kerosene.
Finally, you need a knife and either a grill lighter or some long matches.
Making a candle with an orange
To make a candle, start by cutting the orange in half. Be sure to leave the stem on the inside of the orange intact. The best way to remove the fruit from the peel is to cut around the peel with your knife, but don't cut all the way through the orange. Then you can use your fingers to separate the fruit from the peel and work your way around the entire orange. The fruit should break away from the peel, exposing the stem.
Pour olive oil into the empty orange peel, filling it up roughly halfway. Make sure to lightly coat the stem with some olive oil while you pour, then let the orange sit for a few minutes. You have to give the peel and stem ample time to soak up some of the oil, otherwise it won't burn or stay lit.
After a few minutes, use the lighter to light the tip of the stem. It can take quite a bit of effort to get the stem to light, but it should burn for several hours once it's lit.
Obviously this isn't ideal for daily or even frequent use. And you should consider the risks of burning oil and an open flame in the peel of a fruit before trying this yourself. It should be used cautiously, but it will certainly work as a light source in a pinch -- or it could even provide some creative decoration for a backyard cookout.