Description: Use 1 cup of roasted chestnuts, 1 cup. of water, 1/4 cup of brown sugar, and 3 cl of cognac. Gently heat the water until the sugar is dissolved. Let cool. Place the roasted chestnuts in a clean sealable jar and pour the sugar syrup over the chestnuts. Add the Cognac, stir, and place in the refrigerator for two weeks. Keep in a cool place.