Here’s how you do it:
Take the cherries and raspberries that are in your fridge about to go bad because, in a fit of productivity, you picked them and washed them and then left them in a container in the fridge with no plan for their use.
Take the pits out of the cherries. (we like to use the Lifehacker Bashing Method)
Put them in a pan.
Make a bunch of pan puns.
Cook them for a few minutes with some sugar. (An indeterminate amount; I just poured some in)
While they are cooking, mash them with a potato ricer.
Put them in mason jars in your freezer. In the winter, you can eat them on ice cream and remember how it was once warm.