01 - Cook elbow macaroni in salted boiling water until al dente according to package directions. Drain thoroughly and set aside.
02 - Melt butter in a saucepan over medium heat. Whisk in flour and cook for 1 minute to form a roux. Gradually pour in milk while whisking constantly until smooth. Continue cooking for 2-3 minutes, stirring frequently, until sauce thickens.
03 - Remove saucepan from heat. Stir in shredded sharp cheddar, salt, black pepper, and paprika until cheese is completely melted and sauce is smooth. Add cooked macaroni and mix thoroughly until pasta is evenly coated.
04 - Spread macaroni and cheese mixture evenly onto a baking tray. Refrigerate for at least 1 hour until very firm and completely set.
05 - Scoop chilled macaroni mixture and form into 1.5-inch balls, pressing tightly to compact. Arrange on a parchment-lined baking sheet and freeze for 30 minutes until firm.
06 - Place flour in a shallow bowl. In a second bowl, whisk eggs with milk. In a third bowl, combine panko breadcrumbs and grated Parmesan cheese.
07 - Coat each frozen ball in flour, shaking off excess. Dip into egg mixture, then press firmly into panko-Parmesan mixture to coat completely.
08 - Heat 2 inches of vegetable oil in a deep pot to 350°F. Fry balls in batches without overcrowding, turning occasionally, until deep golden brown and crispy, about 2-3 minutes per batch. Transfer to paper towels to drain.
09 - Serve macaroni and cheese balls immediately while hot and crispy, accompanied by warm marinara sauce for dipping.