Rinse fresh parsley and cilantro under cold water and pat dry. Remove the thick stems.

In a food processor, combine parsley, cilantro, garlic, oregano, red pepper flakes, salt, and black pepper. Pulse until roughly chopped.

Pour olive oil, red wine vinegar, and lemon juice into the food processor. Pulse again until well combined but chunky.

Taste and adjust seasoning with salt, pepper, or vinegar as needed. Pulse briefly to mix adjustments.

Transfer to a serving bowl or jar. Use immediately or refrigerate for up to a week.