You can use bagged baby carrots, but young carrots with tops taste better.
Preheat oven to 450°. Peel carrots, if desired. Trim tops to 1 inch.
Toss carrots with oil, salt, and pepper. Place on a 17- x 12-inch jelly-roll pan.
Bake at 450° for 20 minutes, stirring once. Reduce heat to 325°, and bake, stirring occasionally, 15 minutes or until carrots are browned and tender.