1. Rinse the red currants and put them in a large pot. Add enough water just so that it covers the bottom of the pot.
2. Cook the red currants, stirring frequently, until they’re soft and wilted. Once cooked, pass them through a food mill, discarding the stems and seeds left behind.
3. Weight the puree. For each pound (kilo), add the equivalent amount of sugar to the pot.
4. Mix the puree and the sugar in the pot and cook over medium-high heat, stirring until the sugar is completely dissolved.
5. Once the mixture is at a rolling boil, let it boil for five minutes undisturbed.
6. After five minutes, turn off the heat and skim off any scum. (My frugal co-workers in the kitchen save it and insist it’s delicious on plain yogurt.) If desired, stir in a few drops of kirsch.
7. Ladle the jam into clean jars up to the top and screw on the lids firmly. Turn the jars upside down and let cool completely.