Cut the flesh of the melon into cubes or with a curly knife.
Pour half the sugar and add cognac. Mix well and leave for 3 hours to stir occasionally so that the sugar is completely dissolved.
From the rest of sugar, water and citric acid, boil the syrup, remove the foam during cooking.
Pour melon into boiling syrup and leave it overnight.
After draining all the liquid and cook until it decreases in volume by 1/3. Then add melon and cook for 30 minutes.
Pour the finished jam into sterile jars and roll it up.