Tuna and large fish were traditionally used for “garum”, while small fish were used for “liquamen”. (Though the naming changed with time to reflect production processes rather than raw materials).
Garum was always expensive, while liquamen was initially cheaper and the byproducts of garum production (muria and allec) were the cheapest of them all, and probably the latter was what was given to slaves.
It is available in some specialized supermarkets, I think at least one Spanish version is available in the US. In fact, there are several versions available from the same country, but with modernized recipes.
If you can find a bottle, here’s a recipe for you: https://www.historicalcookingclasses.com/garum/
In fact, some high-end places tend to fabricate their own garum with different bases than fish: https://www.foodandwine.com/condiments/why-chefs-have-loved-garum-since-ancient-times
Or just get some Worcestershire sauce and call it a day.
Or an Asian fish sauce
My friend swears by Thai fish sauce, though he cautions that more than a touch of it will overwhelm the dish.
I’ve been content taking his word for it thus far.
Nothin better than sippin down some shire’ hits the spot for sure
Sippin on 'shire doesn’t hit the spot, it hits everywhere!
And if someone didn’t get enough sauce out of my comment, here’s some discussion on what to call them: Garum, Liquamen and Muria: A new approach to the problem of definition
Explanation: Romans were inordinately fond of a kind of fermented fish sauce they called garum. Like wine, it had low-quality varieties, which, also like low-quality wine, were considered the essential part of even a slave’s rations; and high-quality varieties, which could cost a year’s wages for a common laborer for a single container! The Romans put their fermented fish sauce in everything - on their bread, in their porridge, on their salads, even in their wine! De gustibus non disputandem est - there’s no accounting for taste!
Clearly they were onto something given the plethora of fermented fishes around today.
Still not sure I’d want it in my wine!
The salt and umami really bring out the taste of the lead.
Sauce AND sweetener? Aren’t you a daring one!
If the choice is rotting fish juice or drinking from lead, I’ll take the rotting fish juice.
As someone who just ate steak marinaded in fish sauce last night… This sounds pretty good
What a weird blue tunic.