Measure nuts and garlic into a food processor. Pulse until a rough paste forms. How much of a paste you form will depend on the type of nut you use. (The natural oils from the nut will be released to form the paste).
Add carrot tops and basil, and pulse until everything is in teeny tiny pieces and creates an even thicker, rougher paste.
If your food processor is small (like mine), you might have to stop and move some of the herbs around a bit in order to get them to chop. Don’t worry if it’s not perfect though. You’ll be blending/processing again soon.
Add 1/2 cup olive oil and pulse/blend until the mixture is mostly smooth. If the pesto is too thick, add additional olive oil if desired, 1 Tbsp at a time. I like mine to be spreadable, so I ended up adding another 1/4 cup for 3/4 cup total.
Makes about 1 cup. Store in a glass jar in the fridge. If you’re using quality olive oil, the pesto will likely solidify in the fridge. Bring to room temperature for 10 minutes before using.