Silphium

Here is a recipe, taken from the Roman gourmand Apicius:

Oxygarum (which is similar to garum or rather an acid sauce) is digestible and is composed of:

• 1/2 ounce of pepper
• 3 scruples of Gallic silphium
• 6 scruples of cardamom
• 6 of cumin, 1 scruple of leaves
• 6 scruples of dry mint.

These ingredients are broken singly and crushed and made into a paste bound by honey. When this work is done or whenever you desire add broth and vinegar to taste.

It's a kind of sauce or relish I suppose, that you would use to give whatever you were eating a bit more flavour. This was pretty important in Roman times since there was no refrigeration, and some kind of condiment was often useful for hiding the taste of spoilt or rotten food (hence the popularity of garum).

I don't really recommend trying to make this recipe (though if you're interested, you can find some good Roman recipes here and here). In fact even if you tried you'd find it a bit difficult, especially finding some good Silphium.

Silphium (lasar in Latin) was a very popular herb in Roman times, used to give an exotic flavour both to cooking and to love poetry:

Quaeris quot mihi basiationes
tuae, Lesbia, sint satis superque?
Quam magnus numerus Libyssae harenae
lasarpiciferis iacet Cyrenis
oraclum Iovis inter aestuosi
et Batti veteris sacrum sepulcrum...

You ask, Lesbia, how many of your kisses are enough and more than enough for me? As many as the grains of sand which lie at Cyrene, rich in silphium, between the oracle of Jupiter and the sacred tomb of ancient Battus...

(Catullus 7)

Apparently it had a very strong flavour, but we don't know much more than that about it, as these days it's extinct - eaten to death by the Romans.

A novel I was reading recently, set in ancient Rome, included a sub-plot about the search for silphium, and described it in this way:

‘Real silphium is a thing of the past. That was in the good old days when girls stayed virgins till they married and we all believed the sun was a rather warm god’s chariot.’
‘Yes, everyone nowadays complains that the silphium you can buy is nothing like it used to be…’
‘I’m no expert. Silphium was always the prerogative of the rich.’
‘It’s some kind of herb isn’t it? Imported in ground up form,’ Helena mused. ‘Is it not brought here from Africa?’
‘Not any more.’ I leant on my elbows and stared at her. ‘What’s the wrinkle about
silphium?’ She seemed determined not to tell me, but I knew well enough to reckon this was more than a general knowledge forum. I racked my brains to get it straight, then declared: ‘Silphium, known to those who can’t afford it as Stinking Goat’s Breath-'
‘You made that up!’
‘As I recall, it does smell.
Silphium used to come from Cyrenaica; the Cyrenians protected their monopoly jealously-‘
‘You can see it on coins from Cyrene when you get one palmed in your change at market?’
‘Looks like a bunch of grotesque onions.’
‘The Greeks always loved it?’
‘Yes. We Romans for once allowed ourselves to copy them, since it involved our stomachs which always overrule our national pride. It was powerful stuff, but the ill-advised rural locals where it used to grow let their flocks overgraze the land until the precious crop disappeared. Presumably that causes much grief to their urban relations who used to run the silphium monopoly. Cyrene must be a dead town. The last known shoot was sent to Nero. You can guess what he did with it.’
Helena’s eyes widened. ‘Do I dare?’
‘He ate it. Why, lady; were you imagining some imperial obscenity with the highly prized herbage?’
‘Certainly not – go on.’
‘What’s to add? New sprouts failed to appear. Cyrene declined. Roman cooks mourn. Now we import an inferior strain of silphium from the East, and gourmets at banquets moan about the lost Golden Age when stinking herbs really stank.’

(Two for the Lions, Lindsey Davis)

You can read more about silphium here.