Place the basil, garlic, pine nuts, and parmesan in a food processor and process until finely chopped. With the motor running, gradually add the oil in a thin steady stream until mixture is smooth and well combined.
Transfer to an airtight container and refrigerate.
If you don’t have a food processor, a mortar and pestle can also be used.
Pesto can be placed in an airtight container and placed in the freezer for up to 3 months.
For a nut-free alternative, use sunflower seeds instead of pine nuts
For a vegan alternative, substitute parmesan cheese for a non-dairy cheese
Toss pesto through pasta
Use as a pizza sauce base, mix into salads, top or toss with vegetables and spread it on sandwiches instead of butter.