1. In a saucepan, put the sugar and add 2 tablespoons of water.
2. Cook over low heat, stirring constantly until it forms a caramel.
3. When the caramel is ready, add 1 liter of milk and stir.
4. Turn up to medium heat, add the vanilla, baking soda and keep stirring.
5. Dilute the cornstarch in 1/2 liter of milk, add it to the preparation and keep stirring.
6. It is very important that you keep stirring until you get the desired consistency.
7. When ready, turn off the heat and let it sit at room temperature for a couple of hours.
8. Keep refrigerated, in a container with a lid.