Rinse the parsley and cilantro well to remove any dirt or debris. Shake as much water off the leaves as possible. Pull the parsley and cilantro leaves from their stems, then chop them finely. Mince the garlic.
Combine the olive oil, red wine vinegar, garlic, oregano, cumin, crushed red pepper, salt, chopped parsley, and chopped cilantro in a bowl. Stir to combine.
Use the sauce immediately or refrigerate until ready to use.
*Fresh parsley is one of the main ingredients in this sauce. I like to use Italian parsley, which works best in this recipe as it has a softer texture compared to curly parsley. I also add a bit of fresh cilantro for an extra pop of flavor. But if you’re someone who can’t stand cilantro, you can leave it out and use more parsley instead!**Red wine vinegar is the type of vinegar used in most traditional chimichurri recipes. It's tangy, slightly sweet, and adds the perfect amount of acidity. Apple cider vinegar can be used as a 1:1 substitution in a pinch, but it will give the sauce a slightly fruitier, less traditional flavor.***I use dried oregano to save costs, but if you have fresh available, 1-2 Tbsp fresh oregano leaves can be used in place of the dried (chop them with the other herbs).Spice level: This sauce is mild with just ¼ tsp crushed red pepper. Omit it for no heat, or increase to ½ tsp for more kick. The heat will get a little stronger as the sauce sits, so I recommend tasting again after 10-15 minutes before adding more. You can also add a finely minced jalapeño with the seeds removed, or stir in 1-2 tsp hot sauce for a spicier finish!