Prepare macaroni and cheese according to package or recipe instructions, then transfer to an airtight container and refrigerate at least 12 hours (up to 3 days) so it firms up.
About 15 minutes before shaping, place the container of chilled mac and cheese in the freezer briefly to firm it further.
Place the flour, beaten eggs, and breadcrumbs in three separate shallow bowls.
Preheat the oven to 425°F (218°C). Line two baking sheets with a Silpat, parchment, or foil and drizzle 1 tablespoon of olive oil on each sheet, spreading it to coat the surface.
Use a 1-inch cookie scoop or a tablespoon to portion the chilled mac and cheese into roughly 1-inch balls (hand-shape if needed to make them hold together).
Dredge each ball in flour, dip briefly in beaten egg, then roll in breadcrumbs to coat. Place the coated balls on the prepared baking sheets, about 10 per tray.
Bake for 10 minutes, then remove the trays, drizzle 1 tablespoon olive oil over each tray and spread it, flip each ball, and return to the oven.
Bake an additional 7 to 10 minutes, until the balls are browned and golden all over. Remove from oven and serve immediately with your preferred condiments.