Preheat oven to 375ºF.
Place the beets on a large piece of aluminum foil and drizzle with some EVOO. Season with salt and freshly ground black pepper and fold the foil into a pouch. Roast the beets inside the pouch until tender, about 45 minutes.
When the beets are done roasting, remove them from the pouch and let cool for a few minutes. When they're cool enough to handle, lightly rub the outside of them with a paper towel to remove the skins. Transfer the beets to a food processor and puree them until smooth. Reserve the puree until the risotto is finished cooking.
Bring the water and stock to a boil in a saucepot, then reduce heat to low to keep warm.