Boil macaroni in salted water until al dente. Drain and set aside.
Melt butter in a saucepan over medium heat. Add flour and whisk for 1 minute.
Gradually whisk in warm milk and cook until slightly thickened.
Stir in shredded cheddar cheese and season with salt and pepper.
Mix the cooked pasta with the cheese sauce until fully combined. Refrigerate for at least 2 hours, or until firm enough to shape.
Scoop the chilled mixture and roll into 1.5-inch (4 cm) balls.
Coat each ball in flour, dip in beaten eggs.
Then, roll in breadcrumbs until evenly covered.
In a small bowl, whisk together Greek yogurt, mustard, olive oil, cilantro, salt, and pepper until smooth.
Heat oil to 350°F (175°C). Fry the bites in batches for 2–3 minutes, or until golden brown. Drain on paper towels.
Garnish with chopped parsley, if desired, and serve warm with the dipping sauce.