On a comal/griddle place the tomatoes and the chile de arbol at medium heat. After a few minutes the chiles should become a bit aromatic as they begin to toast. Continuously begin to toss the dried chiles so they toast on most sides. Some blackening is encouraged. Transfer dried chiles to a saucepan with simmering water.
Let the tomatoes dry roast for 10 more minutes. Transfer tomatoes to sauce pan with chiles. Cover and let sit for 5 minutes. . Using a slotted spoon, transfer tomato and chile to blender, along with 1/2 cup of cooking liquid, fresh garlic, lime juice and salt to taste. Blend on high until smooth. Taste for salt.
Notes
Notes: To extend the refrigerator life of the salsa, you can cook the blended salsa at a steady simmer for 10 minutes, mixing in 1 tbsp. of white vinegar as it cooks. Taste for salt.