01 - Boil the elbow macaroni in salted water until al dente, then drain and set aside.
02 - Melt butter in a saucepan over medium heat. Whisk in flour and cook for 1 minute. Gradually whisk in milk, stirring until thickened, about 3 to 4 minutes.
03 - Add cheddar cheese, salt, and black pepper to the sauce. Stir until the cheese is fully melted and smooth.
04 - Add the drained macaroni to the cheese sauce and mix thoroughly. Allow mixture to cool completely.
05 - In a large mixing bowl, combine cooled mac and cheese with cooked rice and grated Parmesan. Blend until unified.
06 - Scoop approximately 2 tablespoons of mixture and shape into a ball. Repeat with the remaining mixture.
07 - Roll each ball in flour, dip in beaten eggs, and coat in panko breadcrumbs.
08 - Heat vegetable oil in a deep pan to 350°F (175°C). Fry rice balls in batches for 2 to 3 minutes, or until golden and crisp. Transfer to paper towels to drain excess oil.
09 - Serve warm. Marinara sauce may be provided for dipping, if desired.