Preheat oven to 425°F and line a baking sheet with parchment paper.
Toss trimmed, peeled, and sliced rainbow carrots with olive oil, salt, and pepper.
Spread carrots on the prepared baking sheet and roast for 20-30 minutes until tender and caramelized. NOTE: The cooking time will depend on the thickness of the slices and your family's personal preferences.
Sprinkle with chopped parsley before serving.
Notes
Storing: Refrigerate cooled roasted carrots in an airtight container for up to 3-4 days.Freezing: Place cooled carrots in a freezer-safe container or bag, removing excess air, and store for up to 2-3 months.Reheating: Thaw frozen carrots overnight in the refrigerator, then reheat in the oven at 350°F (175°C) for 10-15 minutes or microwave on high for 1-2 minutes, stirring halfway through.