Using a blender, blend eggs, milk, and salt; add flour, blending until smooth; then add the melted butter at the end, blending until frothy. Let batter rest for 15 minutes while you preheat the oven.
Preheat the oven to 450 degrees F and place rack in the bottom third position (to make room for tall popovers and to ensure the tops don’t burn!) and another rack in the top position.
Place a 6-slot popover pan on a baking sheet; put on the lower rack of oven for 2 minutes while oven is preheating.
Spray the hot pan all over (including inside the wells and the outside rim) with nonstick cooking spray.
Pour the rested batter evenly into the muffin slots, almost to the top.
Bake the popovers for 20 minutes without opening the oven door. Reduce the heat to 350°F (again without opening the door), and bake for an additional 10 minutes, until they're tall, have "popped" over the tops of the pan, and are a deep, golden brown.
(Without opening the oven door, check them with the oven light during the last few minutes to make sure they’re not over-browning. If so, quickly open the door and put a cookie sheet on that upper rack to shield the popovers' tops from direct heat.)
Remove them from the oven, and pierce the top or bottom of each with the tip of a pairing knife, to release steam and help prevent sogginess.
Slip them out of the pan, split open and serve with butter!
For helpful tips to achieve optimal results, recipe variations, and storage, please refer to the full article.
Nutritional information given is an automatic calculation and can vary based on the exact products you use and any changes you make to the recipe. If these numbers are very important to you, I would recommend calculating them yourself.