Place the vinegar, lemon juice, parsley, oregano, and garlic in a blender and puree. With the motor running, add the olive oil, blending until the sauce comes together. Add the red pepper flakes, and salt and pepper, to taste.
Place in an airtight container and refrigerate for up to 1 day.
Serve at room temperature.
Recipe courtesy of Ingrid Hoffmann, 2007