Published March 1, 2007. From Cook's Illustrated.
Sometimes simplest is really the best.
Update: May 2013
The Back to Basics popcorn popper has been discontinued. We recommend the Nordic Ware Microwave Popcorn Popper as our new winner.
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Bags of microwave popcorn are convenient, but the quality is mediocre. Here's how to spend fewer dollars and barely a minute longer to get a better-tasting result: Pour plain kernels into a microwave popcorn popper and press "start" on your microwave. We tested four all-plastic (glass can shatter and metal can spark) popcorn poppers. After several batches, we realized the simplest popper style was best. Ashy fumes and grease spewed from the "self-buttering" bowl, while a more complicated model demanded disposable (read: need-to-buy-more) cardboard disks. The simpler models yielded fluffy popcorn, with few stragglers at the bottom, and were simple to clean.