Preheat oven to 450F (230C) and lightly grease a 12-count popover pan or two 12 count muffin tin with butter. Place on a foil-lined cookie sheet (to catch any spills) and set aside.

Place eggs in a large bowl and, using an electric mixer, beat on low speed until eggs are frothy and pale yellow (you can do this by hand if you don’t have an electric mixer but it will take longer).

With mixer on low, add milk and melted butter and beat until well-combined.

Sprinkle salt over the batter and stir.

Add flour, stirring on low-speed until batter is completely combined. Batter will be very thin and almost watery and may have small lumps in it.

Evenly divide batter into prepared tin (it's very thin, so I like to use an ice cream scoop to pour the batter, helps keep things less messy), filling each about ⅔-¾ of the way full and transfer to 450F (230C) oven (make sure to keep the foil-lined baking sheet beneath the pan, this will catch any spills!).

If using a popover pan: Bake on 450F (230C) for 20-25 minutes (I find I need 25 minutes if using a light-colored popover pan like the one I used in the video), then, without opening the oven door, reduce the heat to 325F (160C) and bake an additional 15 minutes.

If using a muffin tin: Bake on 450F (230C) for 20 minutes, then, without opening the oven door, reduce heat to 325F (160C) and bake an additional 10-15 minutes.

Remove from oven and serve as soon as they're cool enough to touch. Note that popovers will shrink/deflate as they cool, this is normal!