Wagon Wheels with Broccoli and Parmesan Cheese

Bring a large saucepan of water to a boil. Add salt. Add the broccoli florets and cook until crisp-tender, about 5 minutes. Transfer the broccoli to a bowl with a slotted spoon. Bring the water back to a boil. Add the wagon wheels to the saucepan and cook, stirring occasionally, until al dente. Drain well in a colander. Return the pasta to the saucepan. Add the chicken stock and butter and cook over moderately high heat, stirring gently, until some of the stock is absorbed. Stir in the broccoli and the 1/4 cup of Parmesan; season with salt and pepper and toss. Serve immediately, with additional Parmesan.