Stir the agar-agar flakes into the milk and stir. Bring the milk to a boil. Keep stirring to avoid the agar from sticking to the bottom.Once it comes to a boil, reduce the heat to a simmer and cook until the agar has completely dissolved. Then add sugar and dissolve.
Cool and then add the essence, if using along with the coloring.
Pour it into either molds or into a flat dish.
Refrigerate about 2-3 hrs or until set.
Before serving cut it into shapes of your liking or unmould if using molds.