How do you ensure a tortilla keeps all its contents when making a burrito?

Question

What's the best technique to tuck or close the tortilla when preparing a burrito, to avoid it coming undone whilst eating?

Answer

Folding a burrito is serious business. Get it wrong and you'll end up dumping most of the contents all over the place and look like a burrito noob. Get it right and your hands and plate should be perfectly clean. Be aware that publicly flaunting these skills might lead to many people wanting you to fold their burritos for them.

General Tips

First off, make sure your tortilla is ready to be folded. A cold or dried out tortilla will crack or split much easier than a warm moist tortilla. Second, don't overfill the tortilla. If you have small tortillas you can't try to make a giant burrito and expect that to work out.

How to fold

Now that we have the basics out of the way let's get to folding.

(source)

1. Place the contents in approximately the middle of your partially folded tortilla. This is on its side right now. Leave plenty of room on the ends otherwise you'll most surely have food spilling out once it's folded up. I like to use the bottom end to "tuck" the food in nice and snug by laying it over the food and pulling it in a bit.
2. Fold one end over...
3. then the other end...
4. and then roll the bottom up towards the top. Make sure not to let the food squeeze out. I hold it with my fingers at the crease where the bottom edge that's been folded up meets the food.
5. Keep rolling it up.
6. Om nom nom.

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