01 - Cook elbow macaroni in salted boiling water according to package directions until al dente. Drain thoroughly and set aside.
02 - Melt butter in a saucepan over medium heat. Whisk in flour and cook for 1 minute, stirring constantly to form a smooth paste.
03 - Gradually whisk in whole milk, stirring continuously. Cook until sauce slightly thickens, about 2-3 minutes. Reduce heat to low.
04 - Stir in sharp cheddar, mozzarella, salt, black pepper, and paprika. Continue stirring until all cheese melts completely and sauce becomes smooth and creamy.
05 - Add drained macaroni to the cheese sauce. Mix thoroughly until every piece of pasta is evenly coated.
06 - Spread mixture evenly on a parchment-lined baking sheet. Cover and refrigerate until firm, at least 2 hours. For faster results, freeze for 30 minutes.
07 - Scoop heaping tablespoons of the chilled macaroni mixture. Roll between hands to form 1.5-inch balls, compacting firmly to hold shape.
08 - Set up three shallow bowls: whisk eggs with 2 tbsp milk in the first, place flour in the second, and breadcrumbs in the third.
09 - Dredge each macaroni ball in flour, shaking off excess. Dip into egg mixture, then press into breadcrumbs to coat completely. Place on a clean tray.
10 - Pour vegetable oil into a deep pot to reach 2 inches depth. Heat to 350°F over medium-high heat.
11 - Fry balls in batches of 5-6 for 2-3 minutes, turning occasionally, until golden brown and crispy. Remove with slotted spoon and drain on paper towels.
12 - Arrange fried macaroni balls on a serving platter. Serve immediately with warm marinara sauce for dipping. Garnish with chopped fresh parsley if desired.