InstaMash

InstaMash is a food item found in Fallout 3 and Fallout: New Vegas. It can restore some of your Hit Points, but also gives you a small amount of radiation.

Characteristics
InstaMash is packaged in a white box with blue highlights. A tag-line toward the bottom of the box states that InstaMash comes "With Real Dig-In Flavor!"

The "insta" part of the name most likely indicates that the contents are powdered and requires added water to swell, similar to instant mashed potatoes, though the bottom tag could indicate that the powder is somewhat synthetic to which one could see as a spoof of modern cookery and cheaper production.