Preheat the oven to 400 degrees F. Spray a baking sheet with non-stick cooking spray.
Toss the tomatillos in 1 tablespoon olive oil, sprinkle with salt and pepper and toss to coat.
Roast in the oven until the tomatillos begin to soften and their juices start to ooze out, about 5 - 7 minutes.
Add the roasted tomatillos, cilantro, remaining 2 tablespoons of olive oil to a high speed blender and blend on low until you have a smooth consistency.