Cook the pork. Place the pork, onion, garlic, bay leaves, and salt in a large stockpot. Add 10 cups of water, bring to a boil, then reduce the heat to a gentle simmer. Skim off any foam and impurities that rise to the top. Simmer uncovered for 1 ½ to 2 hours, until the meat is fall-apart tender.
Shred the pork. Use tongs to remove the pork to a cutting board, and shred into bite-sized pieces. Remove the onion, garlic, and bay leaves from the pot, then return the shredded meat to the pot.
Simmer the chiles. Meanwhile, in a small saucepan over medium-high heat, add the dried chiles and enough water to cover them, about 4 cups. Bring to a simmer over medium heat. Simmer for 15 minutes, until the chilies have softened.
Roast the onion and garlic. While the chilies are simmering, add the onion and garlic cloves to a quarter sheet pan. Broil them for 4 to 6 minutes, until lightly charred. Let cool to the touch.
Blend the sauce. Transfer chiles and 1 cup of the water that soaked the chilies to a high-powered blender. Remove the roasted garlic from its peel and add it along with the onion to the blender. Add the oregano and salt. Blend on high for 1 to 2 minutes, until completely smooth. Note: I make and blend the sauce while the pork is cooking and then set it aside.
Simmer together. Pour the red chile sauce and hominy into the stockpot, stir together, and simmer for 1 hour, partially covered, letting the flavors combine.
Serve and garnish. Ladle the pozole into bowls and garnish with your favorite toppings!