01 - Combine mayonnaise, sour cream, lemon juice, vinegar, parsley, chives, tarragon, basil, anchovy fillets if using, garlic, salt, and pepper in a blender or food processor. Blend until completely smooth and creamy. Taste and adjust seasoning as desired. Transfer to a jar and refrigerate until serving.
02 - Place mixed salad greens, cucumber, radishes, and snap peas in a large bowl. Drizzle with 1/2 cup of the prepared Green Goddess dressing and toss gently to coat evenly. Arrange avocado slices on top and sprinkle with fresh herbs. Serve immediately with remaining dressing on the side.