Step 1

Whisk eggs, salt, cayenne, milk, oil, and flour together in a large measuring cup or mixing bowl just until blended.

Step 2

Cover the bowl with plastic wrap and allow to rest for 1 hour on the counter, or in the refrigerator for 2 to 3 hours, up to overnight.

Step 3

Grease 14 nonstick muffin cups with butter, and then mist with cooking spray.

Step 4

Whisk the batter for a few seconds and fill each prepared muffin cup 4/5 full. Sprinkle each evenly with blue cheese.

Step 5

Place the muffin pans into a cold oven with a drip pan set underneath. Set the heat to 450 degrees F (230 degrees C). Bake in the oven until popovers are well browned and fully puffed, about 30 to 35 minutes. Poke each popover with a knife to allow steam to escape. Serve hot.