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Learn how to make Chili Lime Flat Iron Steak with a mouthwatering, flavorful resting butter. This grilled steak looks fancy, but is easy & quick enough for weeknight dinners.

There is nothing like grilled steak on a warm summer evening. I know you agree because you all fell head over heels with our garlic butter steak. And our Mexican steak happens to be one of my favorites. But this Chili Lime Flat Iron Steak is the ULTIMATE in flavor. You will love it!

In this recipe, I’ll show you how to perfectly grill a flat iron steak and season it with a mouthwatering chili lime butter. It’s quick enough for a weeknight dinner, but also special enough to serve to friends and family as they visit.

We’ve partnered with the Ohio Beef Council on this recipe. As always, all opinions are my own.

Why you’ll love this recipe:

Dinner that can be ready in about 30 minutes.
Chili Lime butter that you can make in advance.
High protein in protein. Just 3 ounces of cooked beef gives 25 grams of protein.
Delicious served as a main dish or on a salad.

What is flat iron steak?

Flat iron steak comes from the shoulder area and is cut from the Top Blade. It is considered one of the most tender cuts of steak, second only to the tenderloin. It is full of flavor and great for grilling, pan searing, smoking and stir fry.

Other names for flat iron steak: Book Steak, Butler Steak and Boneless Top Chuck Steak. Can’t find a flat iron steak at the grocery store? Don’t worry! This recipe would also taste great when prepared with flank steak or skirt steak.

How to Grill Flat Iron Steak

To prepare the steak, dust both sides of the steak with salt. Place the steak back in the fridge until the grill is ready.

Heat the grill to a high heat. Aim for about 450-500º Fahrenheit. This is a lean cut of beef and is best of you grill it high so it doesn’t dry out.
Place the steak on the hot grill and press lightly to get sear marks. Flat iron steaks grill quickly at a high heat because they are thin. You’ll only need about 5 minutes per side to get the internal temperature to 140º Fahrenheit for medium rare. (This is dependent on the thickness of the steak so be sure to measure the internal temperature.)
Remove the steak from the grill and place it on a plate.

Always use a meat thermometer when trying to determine beef’s doneness! Temperature should read 145°F for medium rare beef, 160°F for medium, and 170°F for well done. Keep in mind that beef’s internal temperature will continue to rise, even after it’s removed from the grill.

Chili Lime Resting Butter

What gives restaurant steak such an amazing flavor? It’s butter. After steaks come off the grill, it is best to let them rest for 5 minutes before slicing and serving. This will seal in the juices.

Resting butter is butter that you put on top of the steak while it is sitting for 5 minutes. This chili lime resting butter is packed full of flavor due to the ancho and chipotle pepper, limes, garlic and cilantro.

ingredients for chili lime butter in a bowl

Simply combine the butter, lime zest and juices, seasonings, garlic and cilantro and mix well. This can be made up to a day in advance so the flavors can combine. Store the butter in an airtight container in the refrigerator until you’re ready to use it.

How to Slice Flat Iron Steak

Flat iron steaks are long and the grain of the meat runs down the length of the steak. Slice the steak thinly across or against the grain. This breaks down the meat fibers and gives the most tender bite.

What to Serve with Chili Lime Flat Iron Steak

For our family, I served this steak in a bowl with rice, sliced peppers, fresh avocado and corn. Some other side dish options are: