In 4-cup glass measure, combine milk and vanilla. Microwave on high for 2 min. until hot, but not boiling. In a medium bowl, beat the eggs, sugar and salt. until frothy. Slowly add heated milk to egg mix, stirring until blended. Pour into 5-6 oz. custard cups. Microwave uncovered on medium for 6-8 min. Sprinkle brown sugar.