Heat oven to 400 degrees F and arrange a rack in the middle.
Combine broth, rice, squash, puree, and onion in a 3-quart baking dish, season with salt and freshly ground black pepper, and stir to evenly combine. Cover tightly with aluminum foil and bake, stirring occasionally, until most the water has been absorbed and rice granules are puffed, about 35 to 30 minutes.
Remove from oven, stir in remaining ingredients, season to taste and serve.
Recipe courtesy of Aida Mollenkamp