makes 5 half-pints
16 cups (4 pounds) pitted and mashed tart cherries (this should yield about six cups of jammable fruit)
3 cups granulated sugar
1 packet liquid pectin (half a box)
1 teaspoon vanilla extract
1. Add the fruit and sugar to a large non-reactive stock pot. Bring the mixture to a boil and continue to boil for 20 minutes, skimming and removing foam from the surface occasionally.
2. Stir in the pectin packet and boil for an additional five minutes. Stir in the vanilla. When the jam is ready to can, it will appear thick and viscous. You can use these tips to ensure your jam is good to go.
3. Fill your (sterilized) jars, leaving about a 1/4-inch head space. Wipe the rims, apply the lids and rings, and process in a boiling water bath for 10 minutes. (Add 5 minutes processing time per 1000 feet in elevation above sea level; I processed our jars for 15 minutes.)
4. Carefully remove the jars from the water bath and let cool on a towel-lined counter or tabletop. After 24 hours, test the seals to ensure each jar sealed correctly.