1. Bring a small pot of water to a boil and prepare a bowl of ice water nearby.
2. Add the basil leaves to the boiling water and blanch for about 10 seconds, just until the leaves wilt and turn bright green.
3. Transfer immediately the basil to the ice water bath to stop the cooking process. Once cooled, drain well and gently squeeze out excess moisture using a clean kitchen towel or paper towels.
4. Place the blanched basil, olive oil, and optional pinch of salt into a blender or food processor.
5. Blend until completely smooth, about 1–2 minutes. The mixture should be vibrant green and fully combined.

At this point, you have two options:

For a Smooth Basil Oil

Pour the blended mixture through a fine-mesh strainer, cheesecloth, or coffee filter into a clean jar or container. Allow the oil to strain naturally, pressing lightly if needed. Discard the solids.

For a Rustic Basil Oil

Skip the straining step and store the blended mixture as is. The small flecks of basil provide additional texture and concentrated basil flavor, making it ideal for spooning over vegetables, pasta, and grain bowls.

Transfer the basil oil to an airtight container and refrigerate until ready to use.