Add just enough sweetener to the milk to get the right amount of sweetness that you desire. Add a dash of salt and the vanilla beans or extract to add to the taste. Add some agar agar (about 2½ tsp of flakes works with ½ litre of liquid or 1½ tsp powder with ½ litre of liquid). Mix all these and heat in a pot, on low heat and allow to simmer for the agar agar to dissolve. Scoop out a portion in a spoon and place in the refrigerator to check if the agar is sufficient to set the custard. If it does not set, add more agar. Keep in mind that it should not become too hard. Pour into serving bowls and place in the refrigerator for a few hours to set. Garnish with cinnamon and serve.