Toast the pine nuts in a dry skillet over medium-low heat, stirring constantly until golden and fragrant, about 2–3 minutes. Transfer to a plate and let cool.
Wash and thoroughly dry 2 cups packed fresh basil leaves. Place the basil, cooled pine nuts, 2 peeled small garlic cloves, and a pinch of coarse sea salt into a blender or food processor.
Pulse on medium speed until the mixture forms a coarse paste.
Add ½ cup freshly grated Parmigiano-Reggiano cheese and pulse a few more times until just combined.
With the processor running on low, slowly drizzle in ½ cup extra-virgin olive oil until the pesto reaches your desired consistency.
Taste and adjust the salt as needed.