Trim excess fat and gristle from chicken gizzards. Rinse under cold running water.
Place gizzards in a pot of cold water. Bring water and gizzards to a rolling boil; continue to boil for about 15 minutes. Strain gizzards using a colander. Allow to cool.
Meanwhile, combine the flour, seasoned salt, pepper, and garlic powder in a plastic bag. Shake well to combine.
Preheat vegetable oil in a skillet with a lid over medium-high heat to 375 degrees F (190 degrees C).
Thoroughly coat gizzards with flour mixture and shake off excess. Gently lay the coated gizzards in the hot oil. Cook until brown. Reduce heat to medium; cover skillet with lid and cook another 10 minutes. Remove to paper towels to drain.