I make a lot of herb oil with the abundant herbs of summer. I used to make pesto but found that too often I had plenty of basil but no garlic, Parmesan, or pine nuts on hand, so a lot of herbs went to waste. Plus, you can always add the garlic and cheese later. These herb oils last best in the freezer but will keep for weeks in an airtight container in the refrigerator—consider freezing them in smaller containers and pulling one out as you need it. These oils are easiest made with a powerful burr blender, though a regular blender will work well, too. The heat from a regular blender motor will sometimes make the herbs taste bitter immediately after blending. This will dissipate as it cools. If you have a ton of herbs, blend them in batches, making a paste with the salt and oil and then adding more herbs and oil as you go.