Step 1Soak each color of pozole corn overnight in separate bowls of water.
Step 2Drain the pozole corn. Place each color of corn in a separate medium saucepan and add enough water to each to cover. Add 2 tablespoons baking soda to each pot. Bring both to a boil, reduce the heat and simmer for about 2 hours, or until tender, adding more water as needed and skimming foam from the surface. Drain off the cooking water and rinse the corn.
Step 3While the pozole is cooking, soak the dried chiles in hot water. When soft, remove the seeds and dice.
Step 4In a separate stock pot, heat the olive oil. Add the onions, garlic, salt, pepper, oregano, cumin and coriander and cook until the onions are translucent.
Step 5Add the tomatoes, tomatillos, diced chiles, vegetable stock and cooked pozole corn. Bring to a boil, reduce the heat and simmer about 1 1/2 hours. The stew is done when the corn is cooked through.
Step 6Add the lime juice, cilantro and salt and pepper to taste.
Step 7Spoon the pozole into bowls and garnish with queso fresco, toasted pumpkin seeds and the remaining cilantro.