Put the cooked mac and cheese in a sealed tupperware dish and refrigerate until completely chilled, about 2-4 hours. Seriously, you want it COLD.
Fit your food processor with the cutting blade, add the 3 cups of mac to the bowl. Crack and add the eggs, one at a time. Blend the macaroni, at medium speed, for about two minutes.
Prepare a donut pan by spraying each cavity lightly with non-stick cooking spray. Fill each cavity with mac and cheese, keeping in mind to keep the hole clear. Use the back of a spoon to slightly pat it down and away from the center- until the pan is full.
Bake at 350 degrees for 20 minutes, just until the donuts are crisp and firm enough to hold their shape.
Remove the donuts from the oven, let them cool for 2-3 minutes, before removing them from the pan and let them finish completely cooling on a wire rack.
In a dutch oven, preheat the oven to 350 degrees. Fry the donuts for 7-8 minutes, flipping in between, until they're golden brown and crisp on the outside.
Use a pair of tongs to remove the cooked donuts from the oil to a plate lined with paper towels to soak up any excess grease.
Serve the donuts warm, with a side of warm chili for dipping. Ketchup and cheese sauce also pair great for dipping sauces.