Rinse four 2-cup freezer containers and lids with boiling water. Dry thoroughly.
In a large saucepan, combine all ingredients. Bring to a boil. Reduce the heat and let it simmer, stirring occasionally, until the mixture thickens. This will take about 2 hours.
Fill the containers, leaving about 1/2 inch of space at the top. Wipe the edges of the containers clean and cover with lids. Refrigerate for up to 3 weeks or freeze for up to 12 months. Thaw in the refrigerator before serving.