For a lighter version, skip the mayonnaise and add extra lemon; for extra richness, add another tablespoon of olive oil. Swap basil with cilantro for a different herbal profile, or add a few tarragon sprigs for a subtle anise note. Toss with romaine and cucumbers, spoon over quinoa bowls, or use as a dip with carrots, snap peas, and radishes. Drizzle on roasted potatoes or grilled chicken and finish with a squeeze of lemon. Refrigerate 3 to 4 days in a sealed jar; press parchment on the surface to reduce browning, and stir before using. If thick after chilling, whisk in water 1 teaspoon at a time until smooth again. Nutrition varies with yogurt and oil, Greek yogurt keeps protein higher and fat moderate, while avocado adds healthy fats and natural creaminess.