Preheat oven to 375F.

Peel 2 medium-size carrots.

Shave peeled carrots into thin strips using a vegetable peeler.

Trim green tops from 8 green onions; reserve white parts.

Coat a 9-inch round pan with nonstick cooking spray.

Create a striped pattern in the bottom of the pan by alternating carrot strips and green onion greens.

Set the pan aside.

Slice the remaining green onions and the reserved white parts.

Bring 2 cups of salted water to a boil in a large pan.

Add instant polenta to the boiling water.

Cook for 2 to 3 minutes, stirring constantly, until the polenta thickens.

Remove the pan from the heat.

Stir in the sliced onions, grated carrots, thawed green peas, Parmesan cheese, olive oil, minced garlic, and ground nutmeg into the polenta mixture.

Season to taste with salt and pepper.

Spread the polenta mixture evenly over the carrots and onions in the prepared pan.

Bake for 30 to 35 minutes, or until the edges are brown and crisp.

Cool for 10 minutes.

Loosen the galette by running a small knife around the edges of the pan.

Invert the galette onto a serving platter.

If any onion or carrot strips stick to the pan, remove them and rearrange them on top of the galette.

Slice the galette into wedges.

Serve immediately.