Cut a cross-hatch into each of the chestnuts and roast in the oven at 425 degrees for 15-20 minutes.
Let cool completely.
Peel away the husks and put the nut meats into a bowl.
Mash or process the nuts into very small pieces
Cover with 8 oz water and let soak overnight.
Filter through a cheesecloth and fine strainer to extract as much water and oil out of the nuts as possible. Discard the nuts.
Measure the liquid produced and add an equal amount of sugar. I got 6 oz of water, so I added ¾ cup of sugar.
Add 1/16th of a teaspoon of gelatin powder and mix well with a wire whisk.
Chill in the fridge until ready to use.