Heat oven to 425° F. Heat the butter in a medium Dutch oven or ovenproof pot over medium-high heat. Add the shallot, ½ teaspoon salt, and ¼ teaspoon pepper and cook, stirring often, until soft, 3 to 5 minutes. Add the wine and cook, stirring, until almost evaporated, 2 to 3 minutes. Add the broth and rice and bring to a boil.
Cover the pot and transfer to oven. Cook until the rice is tender and creamy, 20 to 25 minutes.
Add the peas, spinach, Parmesan, ½ teaspoon salt, and ¼ teaspoon pepper to the pot and stir to combine. If the risotto is too thick, stir in up to ¼ cup hot water. Sprinkle with additional Parmesan before serving.