Prepare the Rhubarb
If you’re using fresh rhubarb, wash the stalks thoroughly and chop them into small pieces. If using frozen rhubarb, be sure to thaw it and drain off any excess liquid before starting.

Cook the Rhubarb
In a large pot, combine the chopped rhubarb and sugar. Let the mixture rest for about 15 minutes—this helps the rhubarb release its natural juices. Then place the pot over medium heat and bring it to a gentle boil, stirring often. Let it simmer for 10 to 15 minutes, or until the rhubarb is completely soft and begins to break down.

Add the Gelatin
Remove the pot from heat and stir in the gelatin until fully dissolved. Add the lemon juice at this stage if you’d like an extra bright, tangy note.

Cool and Jar the Jam
Let the jam cool slightly, then carefully pour it into sterilized glass jars, leaving about 1/4 inch of headspace at the top. Wipe the rims clean, seal with lids, and allow the jars to cool to room temperature.

Store the Jam
You can store the jam in the refrigerator for up to 3 weeks. If you prefer shelf-stable jam, process the jars in a boiling water bath for 10 minutes, then allow them to cool completely.

Enjoy
Serve your Amish Rhubarb Jam on toast, muffins, biscuits, or scones. It also makes a lovely addition to a cheese board or a sweet swirl in plain yogurt.