Step 1

Put oven rack in middle position and preheat oven to 425°F.

Step 2

Tightly wrap beets foil and roast on a baking sheet until tender, about 1 1/2 hours. Let cool slightly. Peel the beets under running cold water. Place two of the beets in a blender or food processor and process briefly, until somewhat smooth. Dice the remaining beet into 1/2 inch cubes.

Step 3

While beets are cooling, bring broth and water to a simmer in a 2- to 3-quart saucepan.

Step 4

Heat butter in a wide, heavy pot over moderate heat. Cook the garlic and onion until softened and fragrant. Add the rice and cook, stirring constantly, for 1 minute.

Step 5

Add wine and stir until absorbed, about 1 minute. Using a ladle, stir in 1/2 cup warm broth and simmer briskly, stirring constantly, until broth is absorbed. Continue simmering and adding warm broth, one ladle at a time, stirring constantly and letting each addition be absorbed before adding the next, until rice is just tender and creamy-looking, 18 to 22 minutes.

Step 6

Stir in beets, beet puree, vinegar, salt, and pepper and cook, stirring, until heated through.

Step 7

Top bowls of risotto with crumbled goat cheese and dill. Serve immediately.