Grilled Flat Iron Steak with Chimichurri

So you’re basically taking one of the most tender, flavorful cuts of beef, throwing it on the grill, and drowning it (in the best way) with the zippiest, herb-loaded chimichurri sauce. If you’re looking for a way to make weeknight dinner feel like a backyard celebration—or you want a “wow, who made this?!” moment at your next cookout—this grilled flat iron steak with chimichurri is it.

Slices of grilled flat iron steak on a platter, covered with fresh green chimichurri sauce, ready to serve at a summer BBQ or family dinner.

Why You’ll Love Grilled Flat Iron Steak with Chimichurri

Super tender: Flat iron is second only to tenderloin for melt-in-your-mouth texture—no crazy butchering or long marinating required.
Flavor packed: A quick rub brings out the beefy flavor, while the chimichurri adds zing, freshness, and a hit of spice.
Feeds a crowd: Slice it thin and pile it on a platter—this is the kind of meal that brings everyone to the table.
Low-carb, gluten-free, and dairy-free: Comfort food that fits nearly every eating style.

What You Need (Simple, Real Ingredients)

For the Steak:

Flat iron steak (about 1 ½ pounds)
Steak rub or Montreal steak seasoning (store-bought or homemade)

For the Chimichurri Sauce:

Fresh cilantro leaves
Flat-leaf parsley
Fresh garlic
Fresh lemon juice
Red wine vinegar
Aleppo pepper flakes (or red pepper flakes)
Ground cumin
Olive oil
Salt and pepper, to taste

A note on steak: Flat iron is sometimes labeled as “top blade steak.” If you can’t find it, skirt or flank steak work great too—just watch the cook time!

For precise amounts, check the recipe card at the end of the post.

A flat iron steak, fresh cilantro, parsley, garlic, seasonings, and olive oil on a countertop, ready for grilling.

Ingredient Swaps & Customizations

No cilantro? Use all parsley, or sub in fresh basil or mint for a different twist.
No Aleppo pepper? Crushed red pepper flakes or a pinch of cayenne do the trick.
More heat? Add extra pepper flakes or a chopped fresh chili.
Love garlic? Go wild—add an extra clove or two.

How to Make Grilled Flat Iron Steak with Chimichurri (Step-by-Step)

Step-by-Step Instructions

Bring the Steak to Room Temp: Take your flat iron steak out of the fridge 30-45 minutes before grilling. Pat dry and rub all over with your steak seasoning.

A raw flat iron steak on a wooden board, coated with a mix of salt, pepper, and spices, ready to be grilled.

Make the Chimichurri: In a bowl or food processor, combine finely chopped cilantro, parsley, minced garlic, lemon juice, red wine vinegar, pepper flakes, cumin, and olive oil. Season with salt and pepper. Let it sit while you cook the steak—the flavors get even better.

A small bowl of green chimichurri sauce with olive oil, herbs, and red pepper flakes, ready to use as a steak topping.

Preheat Your Grill: Fire up your grill (gas or charcoal) to medium-high heat. You want it hot enough that you can only hold your hand above the grates for about 2-3 seconds.
Grill the Steak: Place the steak on the grill at a 45-degree angle for those classic grill marks. Grill 3-4 minutes, rotate for cross-hatch, and grill another 3-4 minutes. Flip and repeat on the other side until it hits your desired doneness (see the cheat sheet below).
- Rare: 125°F (cool red center)
- Medium-Rare: 135°F (warm red center)
- Medium: 145°F (rosy pink center)

A flat iron steak cooking on a hot grill, seasoned and ready to slice for dinner.

Rest and Slice: Let the steak rest for at least 5 minutes. This keeps all those amazing juices inside. Slice thinly across the grain for the most tender bites.
Serve with Chimichurri: Pile your sliced steak on a platter, spoon the chimichurri all over (or serve it on the side), and watch it disappear.

Sliced grilled steak topped with chimichurri sauce on a white serving plate.

Pro Tips for Flat Iron Steak Perfection

Don’t skip the rest: Giving your steak a few minutes off the grill makes all the difference in juiciness.
Slice against the grain: This shortens the muscle fibers and keeps every bite melt-in-your-mouth tender.
No grill? Use a stovetop grill pan or even a broiler—just keep an eye on the timing.
Make-ahead magic: Chimichurri can be made a day ahead; just give it a stir before serving.

What to Serve with Grilled Flat Iron Steak

Keep it simple and summery, or go full comfort-food mode. Some favorites from my table:

Grilled zucchini or asparagus
Roasted potatoes or sweet potato fries
A crisp cucumber-tomato salad
Warm, crusty bread to soak up extra chimichurri
Steak tacos: Pile leftovers into tortillas with crunchy slaw

How to Store & Use Leftovers

Fridge: Steak and chimichurri keep in separate containers for up to 3 days.
Reheat gently: Warm steak slices in a low oven or in a skillet—just until heated through.
Chimichurri: Stays bright for days and makes an epic marinade or salad dressing.
Leftover steak ideas: Sandwiches, salads, quesadillas, or even breakfast hash.

Personal Note from Chloe at Meat & Melt

I learned to love flat iron steak after a butcher’s suggestion changed my grilling game forever. Since then, this recipe has become my go-to for family nights and special occasions. The chimichurri? Let’s just say I’ve caught people licking the bowl. If you’re nervous about grilling steak, trust me—this recipe will turn you into a grill master.

FAQ

Can I make this steak without a grill?

Absolutely! Use a stovetop grill pan or broil the steak on a sheet pan in the oven. Just watch closely—flat iron cooks fast.

What if I can’t find flat iron steak?

Skirt, flank, or sirloin steak all work here. Adjust the grilling time for thinner cuts, but keep the method the same.

Can I prep chimichurri ahead of time?

Yes! Chimichurri gets even better as it sits. Store it covered in the fridge for up to 3 days—just stir before serving.

How do I know when my steak is done?

A meat thermometer is your best friend. For medium-rare, pull the steak at 135°F and let it rest; it’ll finish cooking off the heat.