Begin by draining the thawed tart red cherries in a colander, letting the juices collect in a bowl for about 1-2 hours.

Prepare your water bath canner by filling it with enough water to cover the jars by at least an inch and bring to a simmer.

Sterilize your canning jars and lids by placing them in boiling water for 10 minutes.

In a large saucepan, whisk together reserved cherry juice, sugar, Clear Jel, and optional cinnamon over medium heat.

Once the mixture thickens and begins to bubble, raise heat to high and boil for about 2 minutes.

Introduce fresh lemon juice, stirring it into the thickened mixture; allow to boil for an additional minute.

Gently fold the drained cherries into the thickened mixture, bringing it back to a gentle boil for 1-2 minutes.

Fill the sterilized jars with the cherry mixture, leaving about 1 inch of headspace.

Process the jars in the water bath canner for 35 minutes, then let them sit for 5 minutes after turning off the heat.

Check the seals on the jars once cooled; store in a cool, dark place.