Make your own pesto ice cubes!
Fresh basil is pricey in the grocery store, easy to grow in the summer garden, and is one herb that completely loses its flavor when dried.
Preserve fresh basil for use in the off season by putting it into a food processor or blender with enough olive oil to make it willing to be glopped into an ice cube tray.

You can add garlic and/or parmesan cheese if you wish, or keep it simple with basil and olive oil, and add the other stuff later.

Once frozen, pop the cubes out into a freezer container, to take out as needed for soups, sauces and more.

Opportunities for substitution are limitless:
chives and melted butter
garlic and butter
nettles instead of basil
you get the idea!