Good cooking question — answering as the UphillTech team:
Your chicken was a rooster and what you found are his testicles. If you are not queasy, this forum entry gives you a picture and some more anatomical details. While animal testicles are typically edible and often a speciality/delicacy, many westerners are not necessarily familiar with them, especially in animals as comparatively small as roosters. Asian (e.g. Chinese) cuisine knows various dishes based on chicken testicles, and there‘s also a Hungarian dish that’s basically a stew/goulash. On the other hand, they have confused unwitting consumers as readily reported by the kind of media that...
Full answer by Stephie: https://cooking.stackexchange.com/a/103393 (CC BY-SA 4.0).
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