1: Blanch 1 cup cleaned and packed herb leaves by placing them in boiling, salted water for 10 seconds and then quickly moving them to an ice bath to stop the cooking.
2: Combine the chilled, blanched herbs with ¼ cup of olive oil in a blender. Blend until very smooth. Transfer the mixture to a strainer lined with a coffee filter or doubled-up cheesecloth and allow it to drain undisturbed (stirring will make the oil cloudy). This process may take a couple of hours.
3: Use the fragrant oil immediately or refrigerate. For best results, serve oil within 2 days as a garnish or as a salad dressing base.