Flank Steak Tacos with Chimichurri Sauce
You will LOVE these steak tacos with chimichurri sauce! Wow - the overnight marinade + the quick cook time, makes it a dinner win! I hope you enjoy!
These Flank Steak Tacos with Chimichurri Sauce are the kind of dinner that turns a regular weeknight into something memorable. Tender, perfectly seared flank steak marinated overnight in a bold orange-garlic-chili rub, sliced thin, and piled into street taco tortillas with creamy avocado, crumbled queso fresco, and a fresh, herby chimichurri sauce that ties everything together. Every bite is a flavor explosion.
The secret weapon here is the overnight marinade. Just 15 minutes of mixing the night before, and the flank steak transforms into something so flavorful and tender it almost cooks itself. The orange juice tenderizes the meat naturally with its enzymes, the chili powder and smoked paprika layer on warm, smoky depth, and the garlic and red onion infuse the steak with classic Mexican-Argentinian flavors.
Then there is the chimichurri. If you have never made chimichurri, you are in for a treat. A bright green, herb-heavy sauce of parsley, cilantro, garlic, red wine vinegar, olive oil, and a kick of red pepper flakes blended in a food processor in 30 seconds. It is what they spoon over steak in Argentina, and once you taste it, you will want to put it on everything (eggs, roasted potatoes, sandwiches, you name it).
Assemble the tacos with all the toppings (sliced avocado, fresh cilantro, crumbled queso fresco, sauteed red onions and jalapenos from the marinade) and pile high. This is a date night dinner, a Friday night with friends dinner, a 'we are eating well tonight' dinner. Let's make it.
📝 Ingredients
- For the Marinade:
- 1 Flank Steak
- 1 Red Onion, sliced
- 1/3 cup extra virgin olive oil (EVOO)
- 1/4 cup orange juice
- 4 garlic cloves, chopped
- 1/2 TBSP chili powder
- 1/2 TBSP smoked paprika
- 1 tsp salt
- For the Chimichurri:
- Handful of Parsley
- Handful of Cilantro
- 1/2 cup EVOO
- 1/3 cup Red Wine Vinegar
- 3 garlic cloves
- 1 tsp red pepper flakes
- 1 tsp Smoked Paprika
- 1/2 tsp Salt
- Tacos:
- Street Taco size tortillas
- Avocado
- Cilantro, chopped
- Queso Fresco, Crumbled
- Sauteed Jalapenos/Red Onion
👩🍳 Directions
- 1
Combine all marinade ingredients together in a gallon Ziplock bag and let it sit overnight or at least 4 hours in the fridge. Remove from fridge 30 minutes before cooking and then pat both sides of the flank steak dry with a paper towel.
- 2
Heat cast iron or large skillet to medium high heat.. Add 2 TBSP of EVOO to the hot skillet and add in your flank steak (set marinade bag to the side). Sear for 4 to 5 minutes on the first side and when seared, flip, and cook for 3 to 4 minutes on the other side. Remove at around 130 degrees (as it will cook more the longer it sits) and cover with foil. Let rest for 10 minutes.
- 3
Turn the pan heat down to medium low, add in diced fresh jalapeno and red onions from the marinade, with a 1/2 cup of juice from the marinade and saute onions/jalapenos until soft. ~ 2 to 3 minutes.
- 4
Prep Chimichurri by adding all ingredients to a mini food processor and blend for 20 to 30 seconds. Taste and alter according to your preference!
- 5
Slice steak against the grain, lay out your taco toppings, and enjoy! Don't forget to heat up the tortillas before serving!
Ingredient Notes & Substitutions
Flank steak: One flank steak (about 1.5 to 2 pounds). Skirt steak or hanger steak are the best substitutes. The marinade tenderizes this naturally tougher cut beautifully.
Marinade ingredients: Olive oil, fresh orange juice, garlic, red onion, chili powder, smoked paprika, salt. The orange juice tenderizes naturally, the spices build the flavor base, the red onion adds sweetness.
Chimichurri ingredients: Fresh parsley and cilantro, olive oil, red wine vinegar, garlic, red pepper flakes, smoked paprika, salt. The herbs and vinegar deliver the bright fresh flavor, the olive oil makes it lush, and the spices add depth.
Street taco tortillas: Small (4 to 6 inch) flour or corn tortillas. Look for ones labeled 'street taco' size. Warm them right before serving.
Avocado: 1 to 2 ripe avocados, sliced. Adds creaminess and balances the bold steak.
Queso fresco: Crumbled. The slightly salty, fresh Mexican cheese is the classic taco topping. Cotija is similar and works as a sub.
Cilantro and sauteed jalapenos/red onion: Fresh cilantro chopped, plus the sauteed onions and jalapenos from the marinade as a topping. These are essential and bring brightness and a little heat.
How to Store, Reheat & Freeze
Store leftover steak separately from the chimichurri and toppings. Sliced steak keeps in an airtight container in the fridge for up to 3 days. Reheat gently in a hot pan for about 1 minute per side just to warm through, never longer or it will overcook.
Chimichurri keeps in an airtight container in the fridge for up to a week. The flavor actually deepens over time. Bring to room temperature before serving so the olive oil loosens up.
Freezing is not recommended for the steak (texture changes) or the chimichurri (the fresh herbs lose their brightness). Make and enjoy fresh.
What to Serve With Flank Steak Tacos
These tacos are a complete meal on their own. Round out the table with a side of Mexican rice, refried or black beans, elote (Mexican street corn), or a simple cucumber and tomato salad with lime vinaigrette. Chips and guacamole or a fresh salsa work as a starter. For drinks, a classic margarita, a Mexican lager, or a sparkling water with lime all pair beautifully. This is restaurant-quality taco night at home.
💡 Tips for Success
- Marinate overnight if you can, 4 hours minimum. The orange juice in the marinade tenderizes the steak naturally and the spices have time to penetrate. Longer marinade equals more flavor.
- Take the steak out of the fridge 30 minutes before cooking. Cold steak hits a hot pan and cooks unevenly. Room temperature steak cooks beautifully.
- Pat the steak completely dry with paper towels before searing. Wet steak steams instead of sears, and you lose that beautiful caramelized crust.
- Get your pan screaming hot before adding the steak. Cast iron is the gold standard. You want a hard sizzle and visible smoke when the steak hits.
- Pull the steak at 130 degrees for medium-rare. It will continue cooking from carryover heat to about 135 to 140 as it rests. Overcooked flank steak gets tough fast.
- Always rest the steak before slicing. 10 minutes covered with foil lets the juices redistribute. Slicing too early means all those flavorful juices end up on the cutting board instead of in your tacos.
- Slice against the grain. Look at the lines in the meat and cut perpendicular to them. This shortens the tough muscle fibers and gives you tender bites.
- Make the chimichurri while the steak rests. Blend everything in a food processor for 20 to 30 seconds. Taste and adjust salt, vinegar, or red pepper flakes to your preference.
❓ Frequently Asked Questions
What if I cannot find flank steak?
Skirt steak is the best substitute. It has a similar flavor and texture and works the same way. Hanger steak is another great option. Avoid lean cuts like sirloin, they will be tough.
How long can I marinate the steak?
4 hours minimum for any real flavor impact. 12 to 24 hours is the sweet spot. Avoid going past 36 hours, the acid in the orange juice can start breaking down the texture too much.
Can I use this on the grill instead?
Absolutely. Grill over high heat for about 4 minutes per side for medium-rare. The marinade is delicious on the grill and gives you that classic charred steak taco flavor.
Is chimichurri spicy?
Mild as written. The red pepper flakes give a gentle warmth, not real heat. For spicier, double the red pepper flakes or add a chopped fresh chili. For milder, reduce or omit the flakes.
Can I make the chimichurri ahead?
Yes. Chimichurri keeps in an airtight container in the fridge for up to a week and the flavor actually deepens over the first day. Bring to room temperature before serving.
What if I do not have a food processor?
Finely chop everything by hand with a sharp knife. The texture will be more rustic but still delicious. A blender works in a pinch but tends to over-puree.
How do I store leftovers?
Store sliced steak separately from the chimichurri and toppings. Steak keeps in an airtight container in the fridge for up to 3 days. Chimichurri for a week. Reheat the steak gently in a hot pan for 1 minute per side just to warm through, you do not want to overcook it.
Made this recipe?
Tag me on Instagram @holleyinthekitchen — I'd love to see it!