Grilled Flank Steak with Miso Butter

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This super simple, mega tender, umami-packed Grilled Flank Steak with Miso Butter will raise the stakes on your steak game.

Grilled Flank Steak with Miso Butter

I’ve been meaning to grill up a delicious steak all summer long. Yes, I know grilling season is well underway, but apartment living here in Singapore has really cramped my grill game. I only occasionally whip out the grill pan for veggies here and there, but rarely use it for actual meat—it just doesn’t do the protein justice!

But today’s Cooking America recipe for the state of Nevada required a steak recipe (more specifically, a chateaubriand, but I improvised with flank steak), so I figured this Grilled Flank Steak with Miso Butter was the ideal opportunity to perfect my indoor grilling skills. And not to toot my own horn or anything, but said skills did not disappoint.

Grilled Flank Steak with Miso Butter

How to Cook Flank Steak

I think flank steak is one of the least intimidating, easiest cuts of beef to cook at home. It’s on the thinner side, so you don’t have to worry as much about doneness, and it’s super versatile and it goes with most any flavor profile. Here are a few tips on how to cook flank steak perfectly:

  • Per the above statement, flank steak benefits from a marinade for flavor and tenderness. And make sure to pat off any of the remaining marinade from the steak with a paper towel before grilling to avoid soggy steak, which is a tragedy and just the worst.

  • Whether you’re using a skillet, grill pan or gas or charcoal grill, medium-high heat will help you achieve the best results and even cooking.

  • If you’re not super familiar with cooking steak, get yourself a meat thermometer! It takes all the guesswork out of doneness, so you can get the perfect medium-rare (or whatever doneness you prefer) each and every time.

  • You want to let your flank steak—or any steak, really—rest at least five minutes after pulling it off the heat. If you slice into it right away, you’ll lose a lot of the steak’s juiciness. Just wait, it’ll be worth the extra few minutes.

  • Last, but perhaps most importantly, you gotta slice that steak against the grain (see instructions below)! The muscle fibers in flank steak are long and can be tough and hard to chew if you don’t slice thinly and against the grain. Slicing them against the grain (i.e. shorter) makes for more tender morsels of beefy goodness!

How to cut Flank Steak

Grilled Flank Steak with Miso Butter

Let’s Make Grilled Flank Steak with Miso Butter

This recipe is super simple and just requires a little bit of upfront marinating time before grilling. If I know I’m making flank steak for dinner, I’ll mix up a marinade in the morning and let the steak marinate in the fridge until dinnertime. But, if you’re crunched for time, 30 minutes of marination should be just fine.

Grilled Flank Steak with Miso Butter

Grilled Flank Steak with Miso Butter

This super simple, mega tender, umami-packed Grilled Flank Steak with Miso Butter will raise the stakes on your steak game.

Print Recipe

Makes 6 servings
Prep time: 5 minute (plus marinating)
Cook time: 10-12 minutes
Total time: 20 minutes


1 flank steak, about 1-1/2 lbs
3 tbsp white miso paste
2 tbsp low sodium soy sauce or coconut aminos
2 tbsp mirin
1 tbsp sesame oil
1 tbsp sriracha
2 cloves garlic, smashed
1-inch knob ginger, peeled and sliced
Freshly ground black pepper
4 tbsp butter, room temperature
Green onions & sesame seeds for topping (optional)


In a bowl, whisk together 2 tablespoons miso paste, soy sauce, mirin, sesame oil, sriracha, garlic, ginger and black pepper in bowl. Place flank steak in a deep glass container with a lid or a large ziptop back, cover with marinade. Place steak in the refrigerator to marinate for at least 30 minutes, or up to 24 hours.

When you’re ready to grill, remove steak from marinade, patting away any extra moisture with a paper towel - you want the steak to be as close to dry as possible before grilling. Grill the flank steak over medium-high heat (either in a grill pan or on an actual grill) for 2-3 minutes per side for medium-rare doneness. Remove flank steak from heat and let it rest for 5-10 minutes before slicing. While the steak is resting, make your miso butter. In a bowl, mix together room temperature butter and the remaining miso paste until combined.

Slice the flank steak against the grain and serve topped with a bit of miso butter, green onions and sesame seeds.