Begin by thoroughly washing your fresh parsley, cilantro, and oregano. Remove the stems and roughly chop them, along with a red onion or shallot and a couple of cloves of garlic. Place all these chopped ingredients into a food processor or blender.

Add the herbs, onion, and garlic into the food processor. Pulse the mixture several times until it's finely minced but not pureed; you want some texture. This should take about 15-20 seconds.

Add red pepper flakes, olive oil, red wine vinegar, fresh lemon juice, and kosher salt to your herb mixture. Pulse again for another 10-15 seconds to combine all the flavors.

Taste the sauce and adjust with more salt or acid if needed. Optionally, add more red pepper flakes or a seeded jalapeño. Pulse gently to blend adjustments.

Transfer the finished Chimichurri Sauce into a glass jar. Let it sit at room temperature for about 15 minutes to allow flavors to meld, or refrigerate for up to 1-2 weeks.