Toast your pine nuts by placing them in a dry small skillet over medium heat for 4-5 minutes, stirring often, until golden brown and toasted. Set aside to cool completely before making the basil pesto.
Make the basil pesto by combining the pine nuts, cheese, lemon juice, zest, garlic, sea salt, and freshly cracked pepper in a food processor; pulse until well chopped.
Add the basil leaves and pulse a few times to chop.
With the food processor running, drizzle in the olive oil and pulse until combined. Taste and add more salt or pepper if needed.
Store this basil pesto in an airtight jar or container and refrigerate for up to 1 week or freeze for up to 2–3 months.
Side Note: To prevent your pesto from browning in the fridge, pour a layer of olive oil on top before tightly sealing the lid.