In a blender or food processor, whirl 1 tablespoon lemon juice, 3 tablespoons olive oil, and 1/4 cup salted, roasted macadamia nuts until coarsely ground. Add 3 tablespoons grated parmesan cheese and 1 1/2 cups lightly packed rinsed and drained fresh basil leaves. Whirl until smooth, scraping container sides as needed. Add salt to taste. If making sauce up to 1 day ahead, cover and chill.