Heat milk to the required temperature. Take half cup of milk and pour it into an air tight container and seal it tight. Vigorously shake the container up and down for 2 mins. This would turn the milk frothy. Reserve it for later.
Add the coffee decoction to the rest of the milk along with sugar and vanilla extract. Mix well until the sugar is dissolved.
Pour the coffee into 2 cups and now pour the frothy milk slowly on top. Sprinkle ¼ teaspoon of brown sugar on top of milk froth on each cup.