What if you had one pot of stew that you just kept cooking and adding ingredients to… forever?

Reddit user shilabula educated the Today I Learned (TIL) community about a medieval dish called “perpetual stew,” attaching this stomach-churning photo as a modern visual aid:

You better hope that’s a fish. (Uhanu/Wikimedia Commons)

While it’s common practice to keep a stew in a slow cooker for a few days at a time (periodically adding a few fresh ingredients to replenish the supply), eternity seems, well, a bit much.

Most descriptions of perpetual stew’s origins appear to be derived from the book Food in History by Reay Tannahill, who defines it as “an ever-changing broth enriched daily with whatever was available.”

Tannahill writes:

“The cauldron was rarely emptied out except in preparation for the meatless weeks of Lent, so that while a hare, hen or pigeon would give it a fine, meaty flavour, the taste of salted pork or cabbage would linger for days, even weeks.”

Okay, so the stew wouldn’t last forever, but keeping leftovers for a full year is “perpetual” enough. Fortunately, most medieval peasants didn’t let their slow-cooking go on quite that long.

As the authors of The Crafts and Culture of a Medieval Manor explain, poorer families in medieval Europe typically ate something called “pottage”: a thick porridge-y, stew-ish concoction comprised of boiled grain, vegetables, scraps of meat or fish, and a regular rotation of “herbs” (before you get excited, it’s not that kind of pottage).

“In some cases,” Joann Jovinelly and Jason Netelkos write, “a kettle of pottage remained on the fire for several days. Ingredients were added as they became available and the thick, soupy meal was in steady supply to feed growing families and guests.”

The concept of reusing the same stew base for an extended period wasn’t unique to Europe. In fact, other cuisines took the idea and applied it for a much longer amount of time.

A similar version of the extreme slow-cooking technique appears in “master stock,” an indefinitely reusable broth found in Asian cuisine.

Vietnamese-Australian chef Luke Nguyen explains this culinary tradition in his book Secrets of the Red Lantern:

“The master stock is a stock that has been kept alive for a great length of time—the master stock at the [Vietnamese restaurant] Red Lantern is now 10 years old and was originally passed down to me by my father. In Vietnamese cooking it is used as a liquid for poaching or braising meat and seafood.”

It may not be an eternity, but 10 years is a pretty impressive lifespan for broth. And if you’re (understandably) worried about food-borne illnesses you might contract from slurping down decade-old soup remnants, don’t worry: Nguyen brings the water to a bacteria-killing boil twice a day.

As many redditors pointed out, other Asian restaurants can claim even older broth:

Despite being a centuries-old tradition in both Eastern and Western cuisines, perpetual stew continues to be a source of fascination for 21st-century foodies.

Back in January, Food and Wine reported on NY chef David Santos’ attempt to tackle the dish, which he recorded by posting regular photos on the stew’s official Twitter account: @perpetual_stew.

You can judge Santos’ success for yourself. Here’s the stew on Day 2:

Day2. Boy was I starving! Today I ate chicken bodies, a bronzino, mushrooms and herb stems. So young but intense! pic.twitter.com/gyo3E3GtG6 — Louro perpetual stew (@perpetual_stew) August 10, 2014

And here’s Day 63:

Day 63- onions&shrimp shells&squash! Fattening up for all of my new dishes #foodculture #chefslife pic.twitter.com/Ukl1E97Zvz — Louro perpetual stew (@perpetual_stew) October 11, 2014

Meanwhile, some members of Reddit’s Slow Cooking community are interested in reviving the medieval tradition—as a way to cut costs, reduce food waste, and avoid having to cook something new every night.

One particularly intriguing take? Perpetual chili.

The next time you make a chili or a stew or a soup or anything else with a broth-like base, don’t just make enough to have leftovers the next day.