Put 1/3 cup kernels in a large brown paper lunch bag and fold the top down several times. Microwave as normal, bag standing up, listening for pops to slow down. Air pops in the bag with no issues.
Salt (and ghee) after you dump it in the bowl.
I have stopped using my whirlypopper.
The process is surprisingly reproducible. I get very few unpopped kernels, usually around 5 of them.
66g of popcorn (that's two servings, according to the label).
2 minutes and 8 seconds.
After cooking, add oil/butter and popcorn salt, then toss. Popcorn salt likes to fall to the bottom, so after tossing, I put on the popper lid, carefully flip it upside down, and shake.
Also, I use a silicone popper, not a paper bag. (Above, I meant to reply to a different comment.)
I'm eating some right now, turns out. When I'm done, I'll edit this comment with a count of unpopped kernels. :-)
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EDIT: 2 unpopped kernels!
Personally I'd just use some kind of metal-free chip clamp instead of actual staples, just to be safe.
I measure a heaping tablespoon of solidified ghee and melt it and add 1 tsp flavacol and toss the popped corn with it to get a similar flavor.
I used to work at a movie theater, this is the way.
I'll give that paper bag trick a try sometime, thanks!