Prep your basil. Rinse and gently pat the basil dry, the drier the leaves, the better the texture.
Toast the pine nuts. In a dry skillet over medium heat, toast the pine nuts until golden and fragrant (about 2–3 minutes). Let them cool slightly.
Blend the base. Add the basil, toasted pine nuts, garlic, and Parmesan to a food processor. Pulse until finely chopped.
Add olive oil. With the processor running, slowly drizzle in the olive oil until the pesto is smooth and creamy.
Season and brighten. Add the lemon juice, salt, and pepper. Pulse again to combine and adjust to taste.
Store it. Spoon the pesto into a clean jar and pour a thin layer of olive oil over the top to keep it fresh. Refrigerate until ready to use.