Sometimes roommates can be a real pain in the ass. When talking resolves nothing, I always like to resort to a few harmless pranks. Especially ones like this where the victim can’t possibly figure out who the prankster is.

If you’re desperate for an easy prank that only takes a minute of preparation, this one’s for you.

The way the prank works is that the baking soda reacts with the vinegar in the ketchup. Also, it isn’t even necessary to use a capped bottle. In the instructional video below, the kid uses a squeeze bottle with an equally great effect.

Ketchup Prank Instructions

REMEMBER: Don’t use a full bottle of ketchup. You’ll want your victim to shake the bottle and cause the baking soda to expand the air inside.