Preheat the oven to 375 degrees. Toss the garlic cloves with the olive oil in a small baking dish. Cover with aluminum foil and bake until the garlic is tender, about 30 minutes. Uncover and bake until the garlic is very soft, about 10 minutes longer. Cool the garlic and peel or squeeze out of the peelings. Puree the pulp in a food processor and set aside.
Bring 4 cups water to a simmer in a medium-size saucepan. Reduce the heat to low, cover and keep hot.
Melt 2 tablespoons of the butter in a heavy large saucepan over medium-high heat. Add the onions and cook, stirring, until tender, about 3 minutes.
Add the rice and stir until golden, about 3 minutes. Add the wine and stir until it is all absorbed, about 2 minutes. Add 1 cup of the hot water. Adjust heat so that the liquid bubbles gently. Stir until liquid is absorbed. Continue adding the hot water, 1 cup at a time, until the rice is just tender and the mixture is very thick, simmering until the liquid is absorbed before each addition. Stir frequently, about 25 minutes. Transfer the risotto to a large bowl and cool for about 30 minutes.
Mix the cheese, parsley and garlic puree into the risotto. Season with salt and pepper. Cover and refrigerate for about 2 hours.
Shape the risotto into 6 patties, each about 3 inches in diameter and three-quarters of an inch thick. Place the risotto cakes on a baking sheet. Cover and refrigerate for at least 1 hour. (At this point, they can be refrigerated for as long as 8 hours.).
Place some flour in a shallow dish. Lightly coat each cake with the flour. Melt 1 tablespoon of the butter in a heavy large skillet over medium heat. Add 2 to 3 cakes and cook until golden brown, about 3 minutes per side. Transfer the cakes to paper towels to drain. Repeat with the remaining 1 tablespoon butter and cakes. Serve warm.