In a large saute pan, heat the oil over medium-high heat. Add the tomatillos,
onion, garlic, and chiles. Cook for about 7 minutes until the tomatillo skins are browned.
Carefully peel the garlic cloves and transfer the mixture to a blender. Add the cilantro and 1 cup of water. Process until smooth, about 2 minutes. Season with salt and pepper, to taste. Pour the salsa into a serving bowl and serve.