1. In a food processor or blender, combine the basil leaves with the seeds, lemon juice and sea salt. Pulse a few times until mixture is reduced in volume and the mixture is well incorporated.
2. Add the garlic and pulse a few times more.
3. Slowly add the olive oil in a constant stream while the blender or food processor is running, stop to scrape down the sides with a rubber spatula.
4. Taste. Add more lemon juice and/or salt if needed.