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How To Cook Marinated Skirt Steak From Costco? (Explained)

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How Do You Cook Kirkland Marinated Skirt Steak?

The Kirkland marinated skirt steak sold at Cosco is easy to cook on a grill or a hot cast iron griddle. Though it’s meant more for things like fajitas than it is for pairing with mashed potatoes and sautéed mushrooms.

How Do You Cook Kirkland Marinated Skirt Steak?

The trick to cooking a flavorful skirt steak is to sear it hot and fast to create a flavorful exterior crust. Yet you still want the interior to be a perfectly pink medium rare. 

The thinness of a skirt steak makes it easy to overcook. One way to hedge your bets is to leave it out on the counter, completely wrapped for 20 minutes or so, to let it warm slightly before grilling.

While the skirt steak sits on the counter you can fire up your grill to 400+ degrees. The goal is to get a ripping hot flame that will sear the exterior in three to five minutes. 

Once the thickest part of the meat reached 130 to 135 degrees, you can remove it from the heat and tent it in heavy-duty aluminum foil with a clean tea towel draped over top. This will keep the meat warm and let the internal juices redistribute back into the meat fibers. 

It’s also the perfect opportunity for you to finish prepping and plating all the other ingredients you need to go with your fajitas. 

When you are ready to serve slice the skirt steak against the grain into thin slices that are less than half an inch thick. This will leave you with short, tender pieces of meat that are easy to chew. If you cut with the grain, the skirt steak strips will be very tough to chew.  

Seasoning It

The Kirkland marinated skirt steak at Costco comes seasoned with southwest seasonings in the vacuum-sealed cryobag. I like that it’s low in salt, but if you’re not afraid of a little extra sodium, you could sprinkle some extra salt and smoked paprika.

Seasoning skirt steak from costco

If you are grilling an unseasoned skirt steak for fajitas or a similar southwestern steak dish, you should use a seasoning blend of salt, fresh cracked black pepper, granulated garlic, smoked paprika, and a few heavy sprinkles of ground cumin. 

Should You Try and Cook a Marinated Skirt Steak from Costco?

The marinated skirt steak at Costco is a great deal for someone who loves tasty grilled beef fajitas but doesn’t want to fuss with seasoning the meat from scratch.

I also appreciate that Kirkland’s processor lightly trims off some of the fat and gristle that you sometimes get with a whole skirt steak. Then they tenderize it with a special type of papaya enzyme, instead of using a food-grade chemical tenderize as some of their competitors do.

If there’s a minor complaint, it’s that the seasoning blend is low in salt. Though I would rather it was under-salted than over-salted.

When Should You Consider Cooking a Marinated Skirt Steak from Costco?

The marinated skirt steak from Costco makes it easy to pull off a great fajitas night. You get a lot of meat in the pack, so it’s probably not ideal for a single person unless you are planning to vacuum seal it and freeze it in cut-down portions.

When Should You Consider Cooking a Marinated Skirt Steak from Costco?

If fajitas aren’t your thing, you could just as easily use the marinated skirt steak for things like gyros with a southwestern flair, or even use it in a stir fry. Just make sure that you cut the steak against the grain to create tender pieces of meat. 

Final Thoughts

The marinated seasoned skirt steak at Costco is a good value. It spares you from having to trim, marinate and season the meat yourself. 

I admit the skirt steak is maybe a little light on the salt. Though it’s easy to add a pinch or two of kosher salt to the seasoned marinade it comes packed with. 

Letting the skirt steak sit out, while still fully wrapped, to warm slightly will help you cook the interior to a proper medium-rare, while still being able to sear the exterior over high heat. After a short rest in heavy-duty aluminum foil, you can slice the meat against the grain into thin strips. 

Final Thoughts

This is an easy way to make grilled fajitas for a family of four or more. If it’s just you and perhaps a significant other, you may need to cut the skirt steak into small portions, before vacuum sealing and freezing. A third of a whole steak is usually enough to make fajitas for two people.