How to Make It
Roast the poblanos directly over a gas flame or under a broiler until charred all over. Transfer the chiles to a bowl, cover with plastic wrap and let cool. Peel, stem and seed the chiles. Transfer to a blender and puree until smooth.
In an enameled cast-iron casserole, heat the oil. Add the onion, cumin, coriander and 4 of the garlic cloves. Cook over low heat until the onion is soft, about 8 minutes. Add the pureed poblanos and cook, stirring, until the mixture thickens, about 5 minutes. Add the spinach and broth and season with salt. Simmer over low heat until slightly reduced and the spinach begins to break down, 15 minutes.
Meanwhile, in a bowl, mash the bread to a paste with the milk. Add the chicken, pork, chile powder, the remaining garlic and 1 teaspoon of salt and gently knead to combine. Roll tablespoons of the mixture into meatballs and add to the chili with the hominy. Simmer until the meatballs are cooked through, about 15 minutes. Stir in the cilantro and serve.