I’m passionate about muffin tins and I’m kind of surprised you aren’t using what I consider to be the best kind- a heavy UNCOATED silver one. Nordicware, for example. I always use liners for cupcakes since they’re more delicate, and I enjoyed reading your test results for that.
But! I wish I could attach a picture of my muffins I baked today. They were a blueberry/blackberry with streusel. Anyway, I didn’t have liners so I sprayed with non stick spray and you’d have to see it to be believe it, they lifted out without even running a knife around the edge! Beautifully. My experience with coated pans is that they stick much worse, even sprayed, than a light one. I also believe the light pans brown more evenly than a coated one.

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