Chop the parsley (and cilantro if using) finely. The more you chop, the more punch you get—no one likes a wilted flavor surprise.
Mince the garlic and toss it in a bowl with the herbs. If you slip with a clove, no big deal—garlic is forgiving
Stir in red wine vinegar, lemon juice (if using), oregano, and red pepper flakes. Give it a quick whisk to mingle the personalities.
Slowly drizzle in olive oil while whisking. The goal is a glossy, cohesive sauce, not a salad dressing that separates at the sight of a fork.
Season with salt and pepper. Taste and adjust; you’re aiming for bright, not brash.
Let it rest for at least 10 minutes if possible. This gives the flavors a chance to become best friends.