Place eggs in a single layer in a medium saucepan. Add enough cold water to come 1 inch above eggs. Bring to boiling over high heat. Reduce heat so water is just below simmering. Cover and cook for 15 minutes; drain. Run cold water over eggs, or place them in ice water until cool enough to handle; drain.
Peel eggs. Remove top quarter of egg; carefully remove yolks. Cover hollowed egg whites; set aside. Place yolks and egg tops in a bowl; mash well with a fork.
Add mayonnaise or light salad dressing, mustard, and vinegar; mix well. Season with salt and pepper. Spoon mashed egg mixture into hollowed egg whites. Top each egg with caviar. Garnish with chervil, if desired. Makes 6 servings.