Drain the hominy, tip into a pot and fill with cold water until just covering the hominy and bring to low boil. Reduce the heat and simmer for 1 hour. Whilst your hominy is cooking away you can make your chili sauce.
In a dry pan over a medium high heat add your de-seeded and de-stemmed chiles de arbol and toast until fragrant and oils begin to release- a few minutes on each side should be enough. Tip the chilies into a saucepan add guajillo powder and 1L/4 cups water. Bring to a simmer, then continue to simmer for up to an hour until water has reduced to approx 1-11/2 inches in depth. Remove from heat and cool slightly, then tip into a blender and blend until smooth. Pass through a sieve if desired to remove any chunky bits of chili skins before adding salt, honey and vinegar and stir well. Taste and adjust seasonings (careful it will be spicy!) and then set aside for later use.
Cube and generously season your pork shoulder. Once the hominy has cooked for an hour, add in the pork, onions and garlic, cover and continue to simmer for a further 2-3 hours until pork is fork-tender and hominy begins to split, topping up with water if necessary (remember you want to create a rich broth as well as tender hominy and pork).
Once you are happy with the texture, taste and adjust seasoning before adding in approx 1/4 cup/ 50ml of your chili sauce, depending on your desired level of heat. A traditional red pasole would add more sauce at this time, but I prefer to serve it the remainder on side and let individuals add in the amount they like.