- 2 oil-packed anchovy fillets, chopped
- 1 garlic clove, finely grated
- 1/2 cup mayonnaise
- 1/2 cup sour cream
- 1/2 cup (loosely packed) basil leaves
- 2 tablespoons parsley leaves with tender stems
- 2 tablespoons tarragon leaves
- 2 tablespoons plus 1 teaspoon fresh lemon juice
- 4 1/2 teaspoons olive oil, plus more
- Kosher salt
- 6 heads of Little Gem lettuce, cores removed, leaves separated
- 2 small watermelon radishes, trimmed, thinly sliced
- Blend anchovies, garlic, mayonnaise, sour cream, basil, parsley, tarragon, 1 Tbsp. lemon juice, and 4 1/2 tsp. oil in a blender until smooth with only a few flecks of green; season dressing with salt.
- Combine lettuce, radishes, and remaining 1 Tbsp. plus 1 tsp. lemon juice in a large bowl, drizzle with oil, and season with salt; toss to combine.
- Top salad with a few spoonfuls of dressing; reserve remaining dressing for another use (like a turkey sandwich!).
- Dressing can be made 1 day ahead. Cover and chill.