"This delicious Mexican salsa (Salsa martajada de tomate verde) is made with fresh tomatillos, chiles de arbol, and garlic. Everything is chargrilled till blackened, imparting a smoky flavor that makes this salsa so special. Serve with tortilla chips, or as an accompaniment to your favorite Mexican meal. [Recipe originally submitted to Allrecipes.com.mx]"
Line a heavy cast iron grill pan or griddle with aluminum foil and place over high heat. Arrange tomatillos, chiles de arbol, and garlic in a single layer on top. Grill until chiles are blackened, turning as necessary, 3 to 5 minutes. Transfer to a bowl. Continue grilling tomatillos and garlic until they are evenly blackened, 8 to 10 minutes more.
Peel garlic and place in a mortar and pestle. Season with salt and pound into a thick paste. Add chiles; pound until smooth. Add as many tomatillos as you can fit in your mortar; pound until chunky. Transfer salsa to a bowl. Repeat with remaining tomatillos, mixing them into the bowl of salsa in batches.