Preheat the oven to 450 degrees Fahrenheit.

Crack the eggs into a blender.

Warm the milk until lukewarm (90-100 degrees).

Melt 2 tablespoons of butter and add it to the blender.

Add the flour to the blender, 1/2 cup at a time, blending briefly between additions.

Blend for 15 seconds after all flour is added.

Let the batter rest for 5 minutes.

Place a popover pan or large muffin tin in the oven to preheat for 5 minutes.

Microwave the macaroni and cheese for 2-3 minutes to remove the chill.

Melt the remaining 1 tablespoon of butter.

Remove the pan from the oven and brush the insides of the cups with melted butter.

Pour a small amount of batter (about 1/4 inch) into the bottom of each cup.

Spoon the warmed macaroni and cheese into the center of each cup, about 1/4 cup per popover.

Pour the remaining batter into the cups, filling them to within 1/4 inch of the top.

Bake in the lower 1/3 of the oven for 15 minutes at 450 degrees Fahrenheit.

Reduce the oven temperature to 350 degrees Fahrenheit and bake for another 20 minutes. Do not open the oven door during baking.

Serve immediately.