Tried this tonight - enjoyed, but *highly* dependent on your choice of jam. Factors to consider: #1) How much sugar is in your jam? #2) Does it contain a pectin? I attempted this with an organic seedless low-sugar jam (only had 7g of cane sugar), which was quite tart but light tasting. Could have used a barspoon of simple, probably. The pectin also makes dissolving the jam difficult - though a homemade non-pectin jam would likely be over-sweet from all the added sugar to macerate into jam.