A blue steak is seared for about a minute on each side over very high heat, leaving a browned crust and a cool, deep-red centre of around 46 to 49C.
It is the rarest way to order a steak, one step below rare, and it tends to divide the table.
This guide covers what blue means, how to cook it, which cuts work best, and what Australia's food safety bodies say before you serve one.
What Is a Blue Steak?
A blue steak is the least-cooked level of steak doneness, seared hard on the outside and barely warmed in the middle. It is also called blue rare, extra rare or bleu, and Australian Beef describes it as the rarest preparation you can choose for a steak.
The name has nothing to do with blue cheese. It refers to the purple-red hue of freshly cut beef, which can look faintly blue before oxygen turns it bright red, and the French term au bleu is widely credited as the origin.
In practical terms, a blue steak reaches an internal temperature of roughly 46 to 49C, against 55 to 60C for rare on the steak temperature chart. That is warm enough to take the chill off the centre, but well below the point where the meat firms up or loses its raw character.
Is a Blue Steak Safe to Eat?
A blue steak is a personal choice for healthy adults using a fresh, intact whole-muscle cut, but it is cooked well below official food safety guidance and carries more risk than a steak cooked to 63C.
The Food Safety Information Council recommends cooking steaks and other whole cuts to at least 63C with a 3 minute rest, and Food Standards Australia New Zealand advises cooking beef mince to 75C.
Bacteria on an intact steak stay on the surface, so searing every face, edges included, matters most, and that surface rule decides whether rare steak is safe. Mince, burgers and needled or mechanically tenderised steak should never be served blue.
FSIC names pregnant women, children under five, older people and anyone with a weakened immune system as more vulnerable to food poisoning, and the same caution applies to raw dishes such as thinly sliced beef carpaccio.
What Is the Difference Between a Blue Steak and a Rare Steak?
A blue steak is seared only, with a cool centre of around 46 to 49C, while a rare steak cooks a little longer to a warm, red centre of 55 to 60C.
Blue keeps a deep, almost raw red colour and the softest, most yielding texture. Rare warms the centre through while keeping most of that tenderness, which many people find a more comfortable starting point.
In the pan, the gap is only a little extra time on each side, so a thermometer is the easiest way to land on the one you want.
Which Cut of Steak Is Best for Cooking Blue?
The best cuts for blue are tender, thick steaks from muscles that do little work, such as eye fillet, sirloin and scotch fillet. Australian Beef recommends that kind of tender, preferably boneless cut, and a piece at least 2.5cm thick lets the outside sear properly while the centre stays cool.
Eye fillet steak is the classic choice, since it is the most tender cut on the animal and lean enough that there is little fat to render. Sirloin, sold in Australia as porterhouse, brings more beefy flavour while still holding a clean blue centre.
Rump also works when it is cut thick, though it is firmer, so slice it thinly across the grain. Richly marbled scotch fillet and Wagyu can be cooked blue, but their fat has little time to soften, so they often eat better at rare to medium rare.
Freshness matters more than the cut name. A blue steak hides nothing, so start with the best beef you can buy, just as you would for a classic steak tartare.
How Do You Cook a Blue Steak?
Sear a steak at least 2.5cm thick in a smoking-hot pan for about 1 minute per side, then give the edges a few seconds each with tongs. You are not cooking the steak through, only building a crust while the inside stays cool.
What Temperature Is a Blue Steak?
A blue steak should read around 46 to 49C in the centre. A meat thermometer is the only reliable check, especially on thicker cuts where judging by feel is far harder.
How Long Do You Cook a Blue Steak?
For a steak about 2.5cm thick, sear for about 1 minute per side, which is the timing Australian Beef recommends, then sear the edges briefly. Thicker cuts may need a few extra seconds a side, but the total time stays short.
How Do You Get a Good Sear Without Overcooking It?
Take the steak out of the fridge at least 15 minutes before cooking, salt both sides, then pat it completely dry so it browns rather than steams. Rub it with a high-smoke-point oil, heat a cast-iron or heavy pan until it smokes, and do not move the steak while the crust forms.
Should You Rest a Blue Steak?
Yes. Australian Beef suggests resting a blue steak for at least 10 to 15 minutes, then reheating the pan and giving it a quick flash on both sides just before serving. The usual rules for resting beef apply, so tent it loosely rather than wrapping it tightly.
How Do You Know When a Blue Steak Is Done?
A blue steak is done when a thermometer reads around 46 to 49C in the centre and the outside is deeply browned on every face. On a steak this rare, a few seconds too long can tip it past the mark, so checking removes the guesswork.
If you prefer feel, a blue steak stays very soft and yielding when pressed, with almost no resistance. When sliced, you want a thin browned band around a cool, deep-red centre.
What Does a Blue Steak Taste Like?
A blue steak tastes soft, tender and intensely beefy, with a savoury, slightly charred crust around a cool, silky centre. It is the same contrast that makes Japanese beef tataki so good.
Because so little happens to the meat, the quality of the cut comes through completely, which is why blue rewards good beef and punishes anything ordinary. Keep the steak seasoning simple so nothing competes with the flavour.
Common Mistakes to Avoid When Cooking a Blue Steak
The most common mistake is putting a fridge-cold steak into a pan that is not hot enough, which greys the outside before a crust can form. Take the steak out at least 15 minutes ahead and heat the pan until it smokes.
Choosing the wrong cut causes problems too. Thin steaks overcook in seconds, and mince or mechanically tenderised meat should never be cooked blue.
Finally, do not forget the edges, and do not slice too soon. Searing only the top and bottom leaves untreated surfaces, and cutting straight away lets the juices run onto the board.
Conclusion
A blue steak comes down to a fresh, intact cut, a smoking-hot pan and a fast sear on every surface.
Choose a thick, tender steak such as eye fillet, check for around 46 to 49C in the centre, and keep blue for healthy adults.
