01 - Cook the elbow macaroni according to package instructions until al dente. Drain thoroughly and set aside.
02 - In a large saucepan over medium heat, melt the butter. Whisk in the flour and cook for 1 minute, stirring constantly to form a smooth paste.
03 - Gradually whisk in the milk, continuing to stir until the mixture thickens, approximately 2-3 minutes. Remove from heat and stir in the sharp cheddar and mozzarella cheeses until completely melted and smooth. Season with salt and pepper.
04 - Add the cooked macaroni to the cheese sauce, stirring until evenly coated. Spread the mixture in an even layer on a baking sheet and refrigerate for at least 2 hours or until firm enough to handle.
05 - Once chilled, scoop approximately 2 tablespoons of the macaroni mixture and roll into balls, about 1 1/2 inches in diameter. Place formed balls on a parchment-lined baking sheet.
06 - Set up three shallow bowls: place the flour in the first, whisk together the eggs and 1 tablespoon milk in the second, and add the panko breadcrumbs to the third.
07 - Roll each macaroni ball in the flour to coat lightly, dip into the egg mixture, then press into the panko breadcrumbs to coat completely. Ensure even coverage for optimal crunch.
08 - Pour vegetable oil into a deep pot or fryer to a depth of 2 inches. Heat to 350°F, monitoring with a thermometer for accuracy.
09 - Fry the breaded balls in batches for 2-3 minutes, turning occasionally, until golden brown and crispy on all sides. Remove with a slotted spoon and drain on paper towels.
10 - Serve immediately while hot and crispy. Pair with marinara sauce, ranch dressing, or spicy ketchup for dipping.