In a medium bowl, combine cold mashed potatoes, shredded cheese, crumbled bacon, chopped chives, garlic powder, salt, and pepper. Mix well until the filling holds its shape when pressed.
Scoop about 1.5 to 2 tablespoons of the mixture and roll into 1.5 to 2-inch balls. If the mix feels too soft, chill it for 15–30 minutes to firm up.
Line up three shallow bowls—one with flour, one with beaten eggs, and one with breadcrumbs.
Roll each ball in flour (shake off excess), dip in egg (let excess drip), then roll in breadcrumbs. Press gently to coat fully.
Place the coated balls on a tray and refrigerate for 30 minutes. This helps them stay firm while frying.
Pour 1–2 inches of oil into a skillet or pot. Heat to 350°F (175°C), using a thermometer for accuracy.
Carefully add a few balls at a time to the hot oil. Fry for 3–5 minutes, turning occasionally, until evenly golden and crisp.
Remove with a slotted spoon and place on paper towels to soak up excess oil.
Enjoy immediately with your favorite dip—sour cream, ranch, or spicy aioli are great options.