I made this today using frozen blueberries. The recipe worked perfectly and it jelled quite solid. If I were to make it again however, I think I might reduce the cinnamon a smidge. I water bathed it for 15 min and I made it into a single one litre bottle. I'm trying to imagine how one might use this condiment. I think it seems like a thick jam, so it'll likely go on toast or bagels. The reason I'm not rating it is because I didn't care for the texture, but I think it's just my own issue of personal preference and I didn't want to taint a perfectly fine recipe that worked well. Thank you for sharing! I'm always fascinated to learn how to make things the 'old way' and still get great results.