Carmelise sugar in a large pan. Sprinkle an even amount of sugar with a setting of 5 out of 10 and, after a few minutes, switch to 7 out of 10. Don't stir the sugar; let it heat slowly. I know it is tempting! This process might take up to 10 minutes.
As soon as sugar melts, add water and mix. The sugar might be set at the bottom. This is normal; wait; it will dissolve quickly.
Add the chestnuts and cook them on the medium heat until the mixture thickens.
Guten Appetit!