Though they come in many varieties, these pans are specifically designed for one thing — to achieve the perfect popover.
You'll find several types of popover pans on the market. Usually made from heavy aluminum or steel, these specialized pans are designed to deliver high, even heat to each popover. The wells are deep and often straight-sided to encourage the popovers to rise straight up out of the pan, and they're set wide apart for good air circulation.
Though the results are impressive, a special pan isn't required for making popovers — you can use a regular muffin pan. It won't achieve the iconic "popped over" shape, but the popovers will still taste delicious.