1. Depending on how you got the basil, it is probably best to wash it. I like to use a salad spinner and actually soak it for about 30 minutes in cold water to make it nice and fresh. Since the basil I was using came from whole plants, roots and all, I washed it 3 times to make sure any and all dirt was out.
2. Remove the visible stems from the parsley and roughly chop it.
3. Add the basil, parsley, nuts, garlic and salt to a food processor (or blender).
4. Process until all the ingredients are chopped to a fine dice.
5. Start the processor again and add the oil in a slow stream until it gets to the desired consistency.
6. Store it in a container with a little olive oil poured over the top to keep it from browning if you are not going to use it right away. If you are using it immediately this step is not really necessary but if you have some left over you can do this and refrigerate it.