Preheat the oven to 450˚F. Line a baking sheet with foil and spray it with cooking spray.
Spread the cauliflower out on the prepared baking sheet. Season it with salt and pepper to taste. Top the cauliflower with another sheet of foil, and roll up the edges to form a sealed package.
Roast the cauliflower for 20 minutes. Remove the top foil, being careful of the steam, and continue roasting the cauliflower until it is tender, another 15 to 20 minutes.
In the bowl of a food processor, combine the cauliflower with the yogurt. Puree until the mixture is smooth. Season with salt and pepper to taste, if desired, and serve.
Source (with permission): Now Eat This! a Ballantine Trade Paperback Original by Rocco DiSpirito (c) 2010 Spirit Media, LLC
Image credit: Kritsada