Preheat the oven to 450°F and line a baking sheet with parchment paper.
Remove the husks from the tomatillos and rinse under cool water to remove the stickiness. Place the tomatillos, onion and pepper on the baking sheet, drizzle with the olive oil and a generous pinch of salt and toss. Place the wrapped garlic on the pan. Roast for 15 minutes or until the tomatillos are soft.
Unwrap the garlic from the foil, peel it, and place in the bowl of a food processor. Add the roasted vegetables, lime juice and cilantro and pulse. If your salsa is too thick, add 1 to 2 tablespoons water to thin to desired consistency. Season to taste.
Serve with chips or with your favorite mexican recipe.
6 medium tomatillos
1/4 medium yellow onion, cut into large chunks
1 serrano or jalapeño pepper, stemmed
2 garlic cloves, unpeeled, wrapped in foil
1 1/2 tablespoons extra-virgin olive oil
1 1/2 tablespoons fresh lime juice
¼ cup chopped cilantro
1/2 to 3/4 teaspoon sea salt to taste