Sous Vide Skirt Steak

January 6, 2017

Sous Vide Skirt Steak

Skirt steak is the cut behind fajitas, churrasco, and asado - thin, beefy, and threaded with long muscle fibers that turn chewy fast if you’re not careful with it. Sous vide solves the two hardest parts of cooking it at home: hitting an exact doneness edge to edge, and, if the water bath runs long enough, softening some of that toughness before the steak ever sees a pan.

There’s a real fork in how people use sous vide on this cut. Some treat it purely as a precision tool: a short two-to-four-hour bath that cooks the steak to an exact temperature and stops there, closer to how you’d treat a strip steak or ribeye. Others treat it the way it’s used on genuinely tough cuts like chuck - holding the meat at temperature for many hours to melt down connective tissue. Skirt steak sits in between: thin enough that pushing past about ten hours starts to turn it mushy, but tough enough that a long bath does noticeably improve the bite. Eight hours lands in the middle of that range.

The sear works the same way regardless of how long the bath ran: pat the steak bone-dry, then hit it hard and fast in a screaming-hot pan or on a grill, a minute or two per side. The water bath handles doneness, the sear handles flavor and color. A neutral, high-smoke-point oil handles the heat better here than olive oil, which starts smoking before the pan is hot enough.

Skirt steak comes as two different cuts - a thicker “outside” skirt and a thinner, tougher “inside” skirt - though most butcher counters and supermarkets just sell it labeled plain “skirt steak” with no distinction, so buy what’s available. However thick the piece turns out, slice it thin and against the grain once it’s rested; skip that step and even a perfectly cooked skirt steak eats tough.

It’s also a good weeknight strategy: start the bath in the morning or right after work, and dinner is five minutes of hot-pan time away. Skirt steak wants something bright alongside it - a spoonful of chimichurri, a squeeze of lime, or the sliced steak folded straight into tacos or fajitas with charred peppers and onions.

Ingredients

Serves 4

900 g skirt steak, trimmed of excess surface fat and cut into pieces to fit the bag
2 tsp kosher salt
½ tsp black pepper, freshly ground
1-2 tbsp neutral oil (vegetable, canola, or refined avocado), for searing

Directions

Season the skirt steak all over with the kosher salt and black pepper. If it’s a long piece, cut it into 2-4 sections so it lies flat.

Seal the steak in a vacuum bag, or a zipper-lock bag using the water-displacement method, in a single layer with as little trapped air as possible.

Preheat a sous vide water bath to 131°F (55°C). Submerge the bagged steak and cook for 8 hours. Anywhere from 2 hours, for a firmer, more steak-like bite, up to about 10 hours, for maximum tenderizing, works - but don’t push past that. Skirt steak is thin enough that it turns mushy well before the 24-hour mark used for thick, tough cuts like chuck.

Lift the bag out of the bath, take out the steak, and pat it completely dry with paper towels. Any surface moisture left on the meat will stop the sear from taking.

Rub the steak lightly with the neutral oil. Heat a cast-iron skillet, or a grill, over high heat until it’s just smoking, about 5 minutes.

Sear the steak hard, 1-2 minutes per side, until it’s deeply browned and charred at the edges - or work it in continuous 15-second flips for the most even crust. Either way, this is a fast, hot sear, not a slow one; the steak is already cooked through.

Rest the steak for 5 minutes, then slice it thinly against the grain. Skirt steak’s long muscle fibers run the length of the cut, and slicing with them instead of across them is the easiest way to turn a well-cooked steak chewy.

Notes

For medium instead of medium-rare, raise the water bath to 140°F (60°C); for medium-well, 150°F (66°C). The time range stays the same either way.

An acidic marinade - citrus juice, vinegar, garlic, herbs - for 4-24 hours before bagging adds flavor. It doesn’t add tenderness, since the water bath already handles that, so treat it as optional.

Leftovers keep 3-4 days in the fridge. Reheat gently, or eat cold sliced into tacos or a salad.