Salt-cured anchovies. They're not rotten at all—they're spectacular! They're perfect on pizza, with fresh tomatoes, and in countless other dishes, either rinsed straight from the jar or melted into a sauce while cooking.

Where I live (a small seaside town), everyone makes their own jars of salt-cured anchovies. They are traditionally sealed with a loose lid consisting of a slate disc with a stone or other weight on top. They need to mature while still being able to breathe, and they must always remain covered by the proper amount of salt.

(The way you describe yours—as extremely smelly and falling apart—doesn't really suggest they're high quality. Normally, a properly cured anchovy should remain almost completely intact, so you can remove the tail and backbone and end up with two whole fillets. The peppercorns are a bit unusual as well.)

I mean, instead of investing so much effort to get glutamate into your food, why not use MSG directly? Sounds like much less hassle? Reminds me of the time when Big Food over here in Germany replaced MSG with "yeast extract" so they could claim that their foods contained no artificial flavor enhancers (although the yeast extract also contains a lot of glutamate).

Rotten? Do you have any more info about this product, even a name? Salted anchovies are common in at least Spain, Italy & Portugal (and you usually rinse off the excess salt and optionally store them in olive oil for a while before consuming), but I've never seen a "rotten" anchovy...