I had to laugh when I saw your question..I just did about a 100 jars of it. The recipe I use is one that my husband's aunt has used for maybe 5 decades.

Choke cherry jelly is hard to jell so it works best to add a couple cups of apple juice or cook the berries with some apples. After the choke cherries are washed about 3 times put in a kettle and add enough water to almost come to the top of the cherries. Boil till they are real soft, don't cover the kettle as you want the water to boil out. Run thru a colander, then run the juice thru a jelly bag. The recipe is:

7 cups juice
7 cups sugar
1 pkg Sure jell plus dab of butter

Add sure jell and butter to juice; bring to boil. Boil one minute. Add sugar and bring to boil again. If you use pure cherry juice boil about 2 minutes, if you add apple juice about 1 1/2 minutes. Let set off heat for about a minute. Skim off foam. Seal in hot sterilized jars.

Keep in mind that if it doesn't jell it makes great syrup. Even after several batches that turn out, I get one every now and then that doesn't jell. Good luck!