MAKE THE STOCK: In a large saucepan, combine the water with the onion, carrots, leek, celery, garlic, bay leaves, thyme, and cloves and bring to a boil. Reduce the heat to moderate, cover and simmer for 50 minutes. Strain the stock into a medium saucepan, cover and keep warm.

MAKE THE RISOTTO: In a medium skillet, melt 2 tablespoons of the butter. Add half of the minced shallot and cook over moderate heat until softened, about 3 minutes. Add the baby greens a handful at a time, stirring between batches until wilted. Season the baby greens with salt and pepper and set aside.

In a large saucepan, melt 1 tablespoon of the butter in the vegetable oil. Add the remaining shallot and cook over moderate heat until softened, about 5 minutes. Add the rice and cook over moderately high heat, stirring to coat the grains, about 2 minutes. Add 1 cup of the warm stock and cook, stirring constantly, until nearly absorbed. Continue adding the stock 1/2 cup at a time, stirring until it is nearly absorbed between additions. The risotto is done when the rice is al dente and suspended in a thick, creamy sauce, about 25 minutes total.

Stir the wilted greens and the remaining 2 tablespoons of butter into the risotto and season with salt and pepper. Serve at once, passing the cheese at the table.

The vegetable stock and the wilted greens can be refrigerated, separately, overnight.