Heat the oven: Heat the oven to 425°F with a rack in the middle. Line a large rimmed sheet pan with parchment for easier cleanup, or leave it bare for slightly better browning.

Peel and seed the squash: Slice off both ends so the squash sits flat and can't roll. Peel it with a sharp Y-peeler, cut it in half lengthwise, and scoop the seeds out of the bulb end with a spoon.

Cut even cubes: Cut the squash into 1-inch cubes, keeping them as close to the same size as you can manage. You should end up with about 6 cups.

Toss with oil and seasoning: Pile the cubes onto the sheet pan and drizzle with the olive oil. Sprinkle on the salt, pepper, and garlic powder, then toss with your hands until every piece looks glossy.

Spread in a single layer: Push the cubes apart so no two are touching. If the pan looks crowded, split everything across two pans. Crowding is the difference between roasted and steamed.

Roast and flip: Roast for 20 minutes, then pull the pan out and flip the cubes with a thin metal spatula. Return it to the oven for 10-15 minutes more, until the edges are deep golden brown and a knife slides into a cube with no resistance.

Season and serve: Taste one and add more salt if it needs it. Scatter the parsley over the top and serve warm.