Preheat the oven to 400 degrees F (204 degrees C). Line a sheet pan with parchment paper, or spray with cooking spray for better browning.
In a large mixing bowl, toss the rutabaga cubes with the olive oil, garlic powder, salt, and pepper.
Spread the pieces evenly on the baking sheet, making sure each piece touches the pan.
Cook rutabaga in the oven for about 25 minutes, until golden brown and tender.