I genuinely don't know.
My one concern is that honey wouldn't handle the extended cooking time, and you could end up with a burnt / bitter end result.
What about...........what about..
Cooking the plums with a little bit more water, reducing, and thickening. Then adding the honey and to reduce further to the thick gloopy stage, putting the saucepan in a larger pan containing simmering water. No direct heat.
Not hot enough? Honey is runny after all, maybe it would not be fast enough.
I do cook but I'm not a cook so any suggestions would help.
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