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, sugar cocoa powder and salt and mix until well combined but still slightly lumpy. Divide the batter among the pans, filling each mold to the top of the rim.
Bake for 30 minutes without opening the oven.
Notes
Recipe adapted from one 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.