Preheat the oven to 425 degrees F (220 degrees C). Line a rimmed baking sheet with parchment.
Place carrots in a microwave-safe bowl. Add water; cover with plastic wrap. Microwave on High until fork tender, 8 to 10 minutes. Drain well.
Toss carrots with oil on the prepared baking sheet. Use a heavy bottomed glass or jar to smash the carrots, taking care not to break them fully apart. Top each carrot evenly with Parmesan cheese and ranch seasoning.
Bake in the preheated oven until crispy and golden brown around the edges, 20 to 25 minutes. Sprinkle with parsley and serve with ranch dressing if desired.