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Craving steak but short on time? I’ve got you covered with this mouthwatering recipe that’s ready in just 30 minutes. The secret? An Instant Pot and flank steak!

I dubbed this chimichurri-style, because it has some Asian twists. Namely, I substituted red wine vinegar for rice vinegar, oregano for scallions, and salt for soy sauce for more umami.

All things I have in my pantry, of course. And it turned out to be a hit!

At first glance, the recipe might seem complicated, but it essentially boils down to the following steps:

  1. Cook potatoes in Instant Pot (10 minutes).
  2. Mash potatoes with seasonings (3 minutes)
  3. Prepare chimichurri sauce. You do this while waiting for your potatoes to cook, so you’re not actually using any extra time…0 minutes. (5 minutes if you wanna be generous.)
  4. Sear steak and grill veggies (8 minutes).
  5. Serve!

Why flank steak?

Flank steak is thinner, chewier, and packs a bold, beefy flavor punch. Because it’s so thin, it takes only 4 minutes to cook! While it may not be as tender as other cuts, it more than makes up for it in taste.

In fact, flank steak is a staple in Asian cuisines, perfect for stir-fries and quick grilled dishes like bulgogi. Its robust flavor means you don’t have to hold back on the sauces – they’ll only enhance the taste.

In this recipe, the tang and fresh herbs from the chimichurri-style sauce not only highlights the steak’s beefy notes, but also keeps it light and refreshing.

If you’ve ever had steaks that left you feeling too greasy, definitely give this recipe a try!

Tips to Keeping Flank Steak Tender

Worried about toughness? Don’t be! Opt for a well-marbled cut, like the ones you can find at Costco (USDA Choice or Prime), to ensure your steak stays juicy and flavorful. Also be careful not to overcook it!

If you’re worried it’s not cooked all the way through, once you take it off the fire, loosely tent with aluminum foil to let it cook the rest of the way with the residual heat.

Pro tip:

Take the guesswork out for your guests and slice your steak across the grain before serving for maximum tenderness and enjoyment. Keep reading to learn more!.

Slicing Tip and Technique

Let’s talk about slicing techniques. Slicing the steak across the grain, as mentioned earlier, is crucial for ensuring tenderness. But what does that mean exactly?

photo depicting how to slice across the grain

When you look closely at a piece of flank steak, you’ll notice lines running through the meat. These lines represent muscle fibers. Slicing perpendicular to these lines (across the grain) shortens the muscle fibers, resulting in a more tender bite. To practice this technique, lay your steak flat on a cutting board and cut against the lines you see. This simple adjustment can make a world of difference in the texture of your steak.

Which Potato Type to Use?

The type of potato matters too! While Yukon gold potatoes are best for their luscious creaminess. Yellow and white potatoes look similar to Yukon gold may look the same, but are different varieties. Read the labels to make sure you’re getting the right ones! If you can’t find them, a mix of yellow and russet potatoes can closely mimic their flavor and texture.

For a healthier and lighter option, consider using half cauliflower in the recipe for the potatoes.

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Chimichurri-style Flank Steak with Creamy Potatoes and Grilled Veggies (30 minutes)

The easiest and quickest steak dinner. Filled with bold beefy flavors and a twist of refreshing and herbaceous tang. Quick enough that you can even pull it off on weeknight!
Prep Time15 minutes
Cook Time15 minutes
Total Time30 minutes
Course: Main Course, Steak Dinner
Cuisine: American, Fusion
Keyword: 30 minute recipe, 30-minute recipes, creamy mashed potatoes, flank steak, steak, steak dinner
Servings: 2


  • Cast-iron skillet
  • Instant Pot or Electric Pressure Cooker


For the Chimichurri-style Sauce:

  • 1/4 cup Italian flat parsley finely chopped (reserve 1/4 for potatoes)
  • 4 stalks scallions finely chopped (reserve 1/4 for potatoes)
  • 1/4 cup avocado oil
  • 1 Tbsp rice vinegar or use 2 Tbsp for extra tanginess
  • 1 Tbsp soy sauce
  • 2 cloves garlic finely minced or pressed

For the IP Potatoes:

  • 1 lb Yukon gold potatoes peeled and quartered
  • 1/2 cup water
  • 1 tsp kosher salt plus more to taste

To serve mashed potatoes:

  • 3 Tbsp heavy cream
  • 1/2 Tbsp butter
  • 2 cloves garlic finely minced or pressed
  • reserved chopped parsley and scallions

For the Steak:

  • 12 oz flank steak
  • 1/2 tsp kosher salt
  • Freshly ground pepper

For the Vegetables:

  • 1 medium bell pepper sliced
  • 1/2 medium red onion sliced
  • 1 Tbsp oil
  • 1 tsp soy sauce
  • 1/2 tsp kosher salt


Preparing the Sides and Sauce:

  • In the Instant Pot, combine potatoes, water, and kosher salt. Pressure cook on high for 6 minutes, then quick release.
  • While potatoes cook, prepare the chimichurri-style sauce. **Reserve 1/4 portion of the chopped parsley and scallions.** Mix the rest with remaining sauce ingredients in a bowl and let it rest for 10 minutes.
  • When potatoes are done, drain and mash them. Add cream, butter, garlic, and reserved chopped parsley and scallions. Mix well, adjust seasoning with salt if needed, and keep warm.

Cooking the Steak and Vegetables:

  • Season the flank steak with kosher salt and pepper.
  • Heat a skillet with oil over medium-high/high heat. Cook steak for about 1 minute per side. After flipping, add 1 Tbsp of chimichurri-style sauce, spread it, and repeat on both sides. Total cook time is around 4 minutes for medium doneness. Set aside to rest for 5 minutes while you cook the vegetables.
  • Scrape off any burnt seasoning with your spatula and discard. Add the oil, vegetables, salt, and soy sauce. Toss to quickly mix, then spread and leave it untouched until nicely charred on the edges (about 1-2 minutes).
  • Slice the rested steak across the grain and transfer to a plate.

Serving Your Delicious Meal:

  • Assemble your plate by topping the steak with remaining chimichurri-style sauce. If you have steak juices, drizzle them over. Serve with charred vegetables and mashed potatoes. Enjoy!


Prep ahead tips:
For the best results, season the steak overnight and refrigerate.
To enhance the flavor of Chimichurri-style Sauce, prepare this ahead and refrigerate it overnight in an airtight container. It can be stored in the fridge for up to 3 weeks. The longer it melds together, the richer the flavor becomes.