In a medium bowl, combine carrots, green onion, bell pepper, and mustard seed.
In a small bowl, combine vinegar, sugar, salt, and pepper. Whisk until sugar dissolves. Gradually whisk in oil until well blended. Add vinegar mixture to carrot mixture, stirring to combine well. Cover, and refrigerate for at least 1 hour.
Recipe by Southern Lady Magazine at https://southernladymagazine.com/carrot-slaw-recipe/