Cook the hominy in a large pot with enough water, sea salt, the head of garlic, and the onion for 1 hour. Add the pork head, pork shoulder, and pork backbone, and continue cooking until the hominy kernels burst and the meat is fully cooked.

Remove the stems and seeds from the guajillo chiles, roast them, then boil until soft. Blend the chiles with a little water, strain, and add to the pozole.

Remove the onion and garlic head from the pot.

Taste and adjust seasoning. Serve the pozole in a bowl and top with chopped lettuce, sliced radishes, finely chopped onion, lime, and tostadas. Some people also like to add diced avocado and a few spoonfuls of hot sauce.

For the special pozole hot sauce, boil arbol chiles in water until very soft. Blend the chiles with water and salt, then strain.