Thoroughly dry mesquite beans, break into pieces, 2" or 3" long.
Put in a pot and add 3 to 4 times as much water as beans. In a crock pot, cook at 200 degrees overnight. Or if in a hurry, cook at 400 degrees for an hour. It is ready when the water looks like tea. Pour the water into a container. Add the same amount of water a second time, josh it a little with a potato masher. Boil it to iced tea color and add it to the first batch of "stock". At this point, you can freeze the stock in a plastic jug for later use.
But to make jelly, get a box of Sure Jel and follow the directions. You'll need 1 box of Sure Jell for 4 cups of juice and 4 cups of sugar. As you make the jelly, add a tablespoon of butter to keep it from boiling over.