Preheat the oven to 375°F. Cut the unmelted butter into 18 small chunks. Place a small chunk of butter at the bottom of each popover mold. Place the pans in the oven while the oven preheats until the butter is completed melted and then remove pans (about 2 minutes).
In a large bowl, whisk together the eggs, milk. Add in the melted butter. Add the flour and salt and mix until well combined but still slightly lumpy. Divide the batter among the pans, filling each mold 1/2 full.
Bake for 45 minutes without opening the oven for large popovers (or 30 minutes for mini popovers).
Notes
Recipe adapted from a recipe found on Umami Girl who adapted it from Gourmet Magazine.
The nutrition information provided are only estimates based on an online nutritional calculator. This is not a comprehensive list of all the nutrients in the recipe (i.e., does not include vitamins, cholesterol, etc). I am not a certified nutritionist. Please consult a nutritionist or doctor for accurate information and any dietary restrictions and concerns you may have.