Preheat oven to 450F.
On a baking sheet, lay tomatillos, jalapenos, and garlic cloves in one layer. Drizzle with olive oil.
Cook for 15-20 minutes or so, until skins of tomatillos and jalapenos are lightly blackened. Turn the broiler on for a few minutes at the end to get a good sear.
Place cooked tomatillos, jalapenos, garlic cloves, juice from one lime, onions, and cilantro into a blender. Blend until all ingredients are mixed and chopped, but not too fine.
Serve with tortilla chips, corn chips, or over enchiladas. Enjoy!