In a medium saucepan, mix together the cornstarch and water until no lumps remain.

Add the cherries, sugar, vanilla, kirsch (if using - or another teaspoon vanilla), and salt.

Stir until combined, turn the heat to medium, and bring to a simmer over medium heat while stirring frequently. While it’s cooking, break up the cherries with the back of a spoon.

It should have thickened quite a bit by the time it starts bubbling, but if it hasn’t, let it simmer a bit more, but not too long, or the cornstarch will break down and make the sauce thin.

You can let it cool completely and then cover and refrigerate for up to 3 days. If you're in a hurry, pour the sauce into a shallow bowl, a pan, or something with a large surface area. Let cool for at least 10 minutes and then place in the fridge or freezer to chill while you prepare the ice cream. It should be totally cool before adding to the ice cream.

In a large mixing bowl, using an electric hand mixer, beat the heavy cream at low or medium speed (to prevent splattering) until it starts to thicken a bit. Then you can turn it up to high speed. Continue beating until you have stiff peaks.

Fold in the powdered sugar, vanilla and salt.

Spoon about 1/3 of the cream mixture over the bottom of the loaf pan (or whatever vessel you’re putting the ice cream in).

Spoon about 1/3 of the cherry sauce on top (it doesn’t need to be an even layer - it all gets mixed up anyway) and then sprinkle over 1/4 cup of very finely chopped chocolate. Use a skewer or knife to swirl it in a bit.

Do this for another 2 layers, ending with chocolate on top.

Cover, place in the freezer and freeze overnight. Can be frozen for up to 3 months. It can be frozen for longer but will start to form ice crystals the longer it sits.