De-Pitting Plums this is very long video on this one, basically, you put the plums in a roasting pan filled it with whole plums, with about 4 cups of water, let it simmer for about 10 minutes.
You just want the skins of the plum so soften so they would be easy to peel if you wanted to. Just leave the skins on for flavor and color.
Once you have squeezed out the pits, you can now use the plums for making jam, crumbles, other baking dishes.. I usually like making them into a sauce then I can them. You just follow the instructions in how to make jam on your Certo box.