When I lived in Buenos Aires, near Uriburu and Corrientes, there was a small parrilla only a couple of blocks from my flat. In the morning, I could walk over and buy an extraordinary vacío sandwich.
It was not breakfast in the usual sense. It was large, hot and substantial enough to keep me going for most of the day.
That kind of sandwich was not unusual in Buenos Aires. Small parrillas appeared in places where you would not necessarily expect to find them, particularly around the city centre. They sold vacío in bread, or sliced on a plate with a simple salad. Nothing elaborate. Just meat, fire and a cook who knew what he was doing.
Well-cooked vacío can be one of the great pleasures of Argentine food.
It is also one of the cuts that causes the most confusion when I try to reproduce an Argentine asado in Britain.
The convenient translation is flank. Anatomically, that puts us in roughly the correct part of the animal. But if you walk into a British butcher and ask for flank steak, what you receive may be quite different from the vacío an Argentine expects to see on the parrilla.
The name is not the whole answer. The piece itself matters.
Vacío is not simply a flank steak
Vacío comes from the abdominal area of the animal, between the ribs and the hindquarter. It has a long, visible grain and a distinctive layer of fat and membrane on the outside.
There is a theory that its Argentine name comes from this being an area vacía de hueso—empty of bone. It is a plausible explanation, although with old names for butcher’s cuts, I am always careful about presenting a good story as an unquestionable fact.
In Chile, the related cut is called tapabarriga, which is wonderfully direct: it covers the belly.
In English, vacío is normally translated as flank. That translation is useful as a starting point, but not as a purchasing instruction.
This is where four terms that sound interchangeable need to be separated:
- Flank can describe the broader abdominal region or a larger butchery section. It does not necessarily identify one finished steak.
- Flank steak is a specific flat muscle prepared from that region. In Britain it is usually sold as a lean, rectangular piece, with the exterior fat and membranes removed, for quick cooking.
- Bavette is the British trade name often used for a coarse-grained steak cut from the thin flank. It tends to be slightly thicker and more irregular than a typical flank steak, although British butchers and restaurants do not always use the two names consistently.
- Vacío is the Argentine way of cutting and preserving a larger piece from this general area—especially its thicker, fattier end—with the exterior fat and cuerito left attached so it can be cooked whole and slowly.
So bavette and flank steak come from the same general part of the animal as vacío, but neither product is automatically the Argentine cut. The anatomy overlaps; the butchery and the intended cooking method do not.
There is one more British term that makes matters worse: thick flank. Despite the name, it comes from the upper hind leg and is closer to what is known elsewhere as beef knuckle. It is not vacío.
When British and Argentine butchers break down a carcass, they do not always follow the same seams or preserve the same sections. British flank may be trimmed into a neat, lean steak. It may have had much of the exterior fat removed. It may be portioned into smaller pieces intended for quick cooking.
That can be a very good piece of beef. It is simply not how we usually understand vacío.
When Argentines talk about putting vacío on the parrilla, we normally mean a substantial whole piece, particularly the thicker end of the flank. We do not generally imagine several small, individual flank steaks being cooked quickly like churrascos.
That difference changes everything: how the meat is trimmed, how it meets the fire, how long it cooks and what the final texture should be.
Do not remove the cuerito
One side of the vacío is covered by a pale, fibrous membrane that Argentines often call the cuerito. Around it there is also a layer of external fat.
A butcher trying to make the cut look clean may be tempted to remove both.
I would not.
The cuerito and fat are not untidy packaging around the “real” meat. They are part of the cut and part of the cooking method. During a long, gentle cook, they protect the surface, help the piece retain its juices and give the vacío its characteristic flavour.
The fat should colour and render slowly. The cuerito can become deeply golden and, when everything goes well, pleasantly crisp in places. Underneath it, the meat remains protected while its tougher fibres relax.
This is one reason that buying a small, completely trimmed flank steak and following an Argentine vacío recipe can be disappointing. The cook has been given a different raw material before the fire has even started.
I often buy a much larger section of beef in London and separate the Argentine cuts myself. It is not because British butchers are wrong. Their customers ask for different things, so they prepare the carcass differently.
But if I want vacío, I need the butcher to understand that I am not asking for a lean rectangle with every irregular edge removed. I want the piece intact, with its exterior fat and membrane still attached.
Sometimes the best way to explain an Argentine cut is not to translate its name. It is to describe where it sits, show a photograph and explain how you intend to cook it.
A cut made for a slow parrilla
Vacío has a clear, substantial grain. That fibre gives it texture and a strong beef flavour, but it also means the cut needs patience.
This is not fillet. It should not try to be.
Fillet is tender almost regardless of what the cook does to it. Vacío asks for some judgement. Cook it too fast and the outside can burn while the fibres remain tight. Cut it in the wrong direction and even a properly cooked piece will feel tougher than it is. Remove its protection and leave it too long over aggressive heat, and it dries out.
On an Argentine parrilla, I cook vacío whole and slowly. The fattier, membranous side faces the heat first. The fire should be moderate and controlled—enough to cook continuously and render the fat, but not so fierce that the exterior burns before the heat moves through the piece.
Depending on the size of the vacío and the parrilla, that may mean a gentle bed of embers beneath it, or much of the heat distributed around it rather than concentrated directly below. I normally turn the piece only when the first side has developed the colour and protection I am looking for.
Recipes that promise a universal cooking time for vacío make me suspicious. A thin piece and a thick 2.5-kilogram piece are not the same. Neither are two fires. The distance from the embers, the strength of the heat, the age and structure of the meat and even the weather around an open parrilla all affect the cooking.
You have to look at the fat, feel the resistance of the meat and understand what the fire has been doing.
That is not mysticism. It is simply cooking.
Salt is enough. Some asadores use coarse salt; others apply a light salmuera during the cook. I sometimes use salmuera with large pieces, but the objective is never to cover the taste with a marinade or a collection of spices.
The beef must remain the principal flavour.
It should not eat like a ribeye
There is a habit in modern steak cooking of treating every cut as though its highest purpose were to be red in the centre, sliced dramatically and arranged across a plate.
I do not think that always suits vacío.
Vacío needs enough time for its structure to change. That does not mean cooking it until it is grey and dry, but it does mean respecting what the cut is. A very thick piece served rare may look impressive in a photograph while remaining tight and difficult to eat.
Traditionally, vacío is often cooked further than a ribeye or fillet would be. The aim is meat that is properly cooked through its fibres but remains juicy because it has been handled gently and protected by its fat and cuerito.
Then it must be sliced across the grain.
This last point is not decorative advice. Long muscle fibres can make a slice feel unnecessarily tough. Cutting perpendicular to them shortens those fibres and makes the meat much more pleasant to eat.
If I cut into a large vacío and discover that a thicker section needs a little more time, I put those slices back on the parrilla.
There is no shame in that. The meat matters more than the asador’s pride.
Why vacío belongs beside tira de asado
If I had to choose the cuts that define a traditional Argentine parrilla, vacío and tira de asado would be at the centre of it.
They work well together. The ribs bring bone, fat and the deep flavour that develops around them. Vacío brings a completely different texture: long fibres, rendered exterior fat and slices that absorb the juices collected on the board.
Neither is a luxury cut in the conventional steakhouse sense. That is precisely why they tell you more about the asador.
An expensive ribeye already contains tenderness and marbling. The cook’s main job is not to ruin it. Vacío has more character, but it needs more understanding. It rewards control of the fire, patience and correct carving.
I would not describe it as soft like butter, and I do not think that should be the universal ambition for beef. You have to chew vacío. In return, it gives you an intensity of flavour and a personality that fillet simply does not have.
For me, that is more interesting than tenderness alone.
The vacío sandwich
Vacío does not belong only to the large Sunday asado.
It also belongs to the small parrillas of Buenos Aires: the places feeding office workers, taxi drivers, neighbours and anyone who follows the smell of meat over embers. There, the same cut can be sliced and pushed into bread, perhaps with chimichurri or salsa criolla.
You may see the word vaciopán used for this, and people will understand it. But in ordinary conversation, I would be more likely to ask for un sándwich de vacío.
The sandwich I remember near Uriburu and Corrientes was not interesting because somebody had reinvented it. It was interesting because they had not.
The bread had to hold the meat and its juices. The vacío had to be cut thinly enough to bite without pulling the entire filling out at once. The flavour came from the parrilla, the fat and the browned edges.
It was simple food, but simple does not mean easy. A badly cut or badly cooked vacío makes a terrible sandwich. A good one needs very little help.
Even now, living in London and cooking more elaborate versions of modern Argentine food, that sandwich remains part of how I understand the cut.
Vacío can sit proudly in the centre of a large parrillada. It can also be handed through the window of a tiny city parrilla wrapped in paper.
Both versions belong to the same culture.
Finding vacío in Britain
If you want to cook vacío in Britain, I would begin with a butcher rather than a supermarket label.
Explain that you want a large, whole piece from the thin flank area, preferably the thicker end, and that it will be cooked slowly rather than divided into steaks. Ask for the exterior fat and the membrane to be left in place. If possible, show the butcher a photograph of an Argentine vacío before it has been trimmed.
This is how I would ask for it:
I’m looking for a whole boneless thin flank, untrimmed, with the outer fat and membrane left on. I don’t want it portioned or trimmed into bavette or flank steaks.
Do not assume that the words flank steak will communicate all of that.
Look for a piece that is substantial enough to cook as a single cut, with a healthy colour and clean, pale fat. The exact weight matters less than the relationship between thickness and cooking method, although a smaller whole vacío is usually easier to manage than an enormous piece from an older animal.
Most importantly, do not buy a beautiful, completely trimmed British flank steak and then blame the Argentine method when it behaves differently.
The translation may be close. The cut is not necessarily the same.
This problem is one of the reasons I enjoy talking about Argentine butchery. Cuts carry the history of how a culture cooks. Change the way the animal is divided and you also change the dishes that appear around it.
When I look at a whole vacío, I do not see an oversized flank steak waiting to be portioned.
I see a piece that belongs intact over a slow fire. I see it beside the tira de asado, cooking while people gather around the parrilla. And I still see that sandwich in Buenos Aires, two blocks from home, substantial enough to take care of the rest of my day.
If you are trying to find vacío in Britain, or you have received a cut from your butcher and are not sure whether it is the right one, you are welcome to contact me. Send me a photograph. I am always happy to talk about meat, fire and the strange business of translating an Argentine parrilla into British butchery.
And if your butcher gives you something completely different, do not be too hard on them.
They probably translated the word correctly.