- 1 cup (packed) whole fresh basil leaves plus 3 tablespoons thinly sliced fresh basil
- 1/2 cup plus 2 tablespoons extra-virgin olive oil
- 2 1/2 tablespoons unseasoned rice vinegar
- 2 tablespoons Dijon mustard
- 1/4 cup chopped red onion
- 2 pounds medium Yukon Gold potatoes, peeled
- Blanch whole basil leaves in boiling water for 1 minute; drain. Run under cold water; drain and squeeze out any excess water. Place basil in kitchen towel and squeeze out water. Transfer basil to processor. Add 1/2 cup oil; process until basil is very finely chopped. Transfer to small bowl and season with salt. DO AHEAD Basil oil can be made 2 days ahead. Cover and chill. Bring to room temperature before using.
- Whisk vinegar and mustard in small bowl to blend. Gradually whisk in remaining 2 tablespoons olive oil. Stir in red onion and 3 tablespoons thinly sliced basil. Season dressing to taste with salt and pepper.
- Place potatoes in large saucepan. Add enough water to cover potatoes by 1 inch. Bring to boil, reduce heat to medium, and simmer until tender, about 17 minutes. Drain. Let potatoes stand until just cool enough to handle. Cut into 3/4-inch cubes and place in large bowl. Drizzle dressing over warm potatoes and toss gently to coat. Pour basil oil over potatoes; toss gently to coat. Serve potato salad warm or at room temperature.