Testicles de John Spottiswood

The most popular seem to be bull testicles = Rocky Mountain oysters = bollocks = swinging beef = Montana tendergroin = bull balls = huevos del toro, but those from smaller, younger animals are reputed to have a milder flavor. Well regarded are l amb testicles = lamb fry = lamb fries = lamb balls, and calf fry = calf balls = calf testicles. Hispanic markets are a good source.