Crunchy mutfruit

 is a food item found in Fallout 3 and Fallout: New Vegas.

Characteristics
Crunchy mutfruit has a different appearance than the standard mutfruit, it can restore some of your hit points, but also gives you a small amount of radiation. Additionally, in Fallout: New Vegas it can stave off starvation and be used in the Wasteland Omelet recipe.

Fallout 3
Crunchy mutfruits are fairly common and can be found at any of a number of camps and other dwellings. Guaranteed locations include:
 * On a table in Billy Creel's house (Megaton).
 * Caravan traders (specifically, Doc Hoff).
 * Gary's Galley.
 * From the repeatable quest Zip's Nuka Fix.

Fallout: New Vegas

 * Great Khan longhouse in Red Rock Canyon, both in the pantry and on the table.
 * Nellis Air Force Base - In the Boomer schoolhouse on the teacher's desk. Must be stolen.
 * The Tops restaurant kitchen behind a locked door.
 * The Tops presidential suite - In a bowl of fruit on the counter near to where Benny sits during the quest Ring-a-Ding-Ding!.