3 Tablespoons fresh basil, chopped (plus leaves to garnish)
2 Tablespoons flat-leaf parsley, chopped
Freshly ground black pepper to taste
Put potatoes in a large pot, cover with water and bring to a boil over high heat. Add some salt and continue cooking until potatoes are just tender when pierced with a knife. Begin testing around 8 minutes. Times will vary with size of potatoes. Drain and let cool.
When cool, cut into fourths or eighths. Combine cucumber, pepper and onion and Feta cheese with potatoes in a large bowl.
Whisk Mustard and vinegar together in a small bowl. In a slow stream, whisk Roasted Garlic Oil into mixture to form an emulsion. Stir in basil and parsley. Pour dressing over salad; toss to blend, then season with salt and pepper. Add a couple of fresh basil leaves as garnish and serve at once.