Slit 6 dried guajillo chiles, 6 dried mora chiles, and 6 dried árbol chiles from top to bottom. Remove and discard stems and most of the seeds. Heat a cast-iron skillet over medium-high heat; cook each chile, pressing it down firmly and flipping once, until lightly toasted, 3–5 seconds on each side. Transfer chiles to a plate. Bring a large pot of water to a boil, add chiles, 1 small whole tomato, 3 cloves garlic, and 1⁄2 small white onion, reduce heat to medium, and simmer, removing each ingredient as it becomes tender, 3–4 minutes for tomato, 5–6 minutes for onion, 10–12 minutes for chiles and garlic. Purée the vegetables and chiles with 1⁄4 cup water in a food processor into a coarse salsa. Season with salt to taste. Serve with the Squash Blossom Quesadilla, if you like. Makes 2 cups.