Ginger plum muffins

Quite a while ago I made some peach muffins spiked with ginger and they turned out absolutely delicious; now I've learned that ginger goes really well with plums, too, again in muffin form (but please don't ask me to pick a favorite). ;)

Ginger plum muffins
slightly adapted from the delicious Tate's Bake Shop: Baking For Friends

150ml whole milk
6 tablespoons (85g) unsalted butter, melted
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