½ small white onion, halved lengthwise, keeping root intact
½ head of garlic, unpeeled, halved crosswise
1 jalapeño
1 pound husked tomatillos
1 tablespoon vegetable oil
½ bunch cilantro leaves and tender stems
¼ cup fresh lime juice, plus more
Kosher salt; freshly ground pepper
Heat your grill for medium-high heat. Place onion, garlic, jalapeño, tomatillos in a large grillin’ basket. Grill vegetables, turning often, until tender and charred, 5–8 minutes. Transfer to a plate and let cool slightly.
Squeeze garlic cloves into a food processor and pulse with onion, stemmed jalapeño, tomatillos, cilantro, and lime juice until a chunky sauce forms; season with kosher salt, freshly ground black pepper, and more lime juice, if desired.
Do Ahead:Salsa verde can be made 5 days ahead. Cover and chill.
