How to Make It
In a large bowl, using a rubber spatula, stir the macaroni and cheese with the cheddar, Gouda, sour cream, 1 teaspoon of salt and 1/4 teaspoon of pepper until well combined. Scoop the macaroni mixture into thirty-five 2-tablespoon balls. Transfer to a rimmed baking sheet and freeze until firm, about 30 minutes.
Put the flour, eggs and panko in 3 separate shallow bowls. Season the flour with 1 teaspoon of salt and 1/2 teaspoon of pepper. Beat the eggs with the hot sauce. Working with a few at a time, dust the mac and cheese bites with flour, tapping off the excess, then dip them in the eggs and coat with panko, pressing to help the crumbs adhere. Return the mac and cheese bites to the baking sheet.
In a large saucepan, heat 1 1/2 inches of oil to 350°. Fry the mac and cheese bites in batches until golden brown and tender, about 5 minutes. Transfer to a wire rack lined with paper towels to drain. Season with salt.
In a small bowl, whisk the ketchup with the Sriracha and serve with the warm mac and cheese bites.