Mix Egg Replacer and water together. Stir in sugar and vanilla; beat until stiff, about 10 minutes. Spoon onto chilled pie just before serving. Makes about 1 cup. PER 1 1/2 TABLESPOON SERVING: 20 CAL.; 0 PROT.; 0 FAT; 5G CARB.; 0 CHOL.; 1 MG SOD.; 0 FIBER.