De-husk the tomatillos and give them a good rinse. I usually de-stem them as well. Add the tomatillos to a roasting pan along with the rinsed Poblano and roast it all in the oven (400F) for a half hour or so.
Add the remaining green sauce ingredients to a blender: 1/2 peeled onion, 1 de-stemmed and rinsed jalapeno, 2 peeled garlic cloves, and 10-12 sprigs of rinsed cilantro. I usually just twist off and discard the bottom, thicker portions of the cilantro but use the upper stems that hold the leaves together. Note; you can start with just 1/2 jalapeno if you want a milder version.
When the tomatillos and Poblano are done roasting you can remove them from the oven and let 'em cool for a bit. Then de-stem and de-seed the Poblano. You can also pull off and discard any puffy bits of skin from the Poblano, but don't worry about getting rid of every last bit.
Add the tomatillos and Poblano to the blender -- the other green sauce ingredients should already be in the blender (step #2). Combine well. Heat up a glug of oil in your soup pot over medium heat. Add the mixture from the blender and cook for a few minutes over medium heat, stirring regularly.
Drain and rinse a single can of hominy. Add the hominy to the green sauce along with the final ingredients: 4 cups stock, 1/2 teaspoon Mexican oregano, pinch of cumin (optional), 1/2 teaspoon salt, and some freshly cracked black pepper.
Bring this mixture to a simmer and take a taste for seasoning. I added another generous pinch of salt at this point, but keep in mind the salt level will depend on which stock you're using. I used this Better Vegetable Stock. Let simmer for 10-15 minutes. As the Pozole simmers you can build the fixings. For this batch I tossed some thinly sliced cabbage and avocado in freshly squeezed lime juice (and a pinch of salt). I also chopped up some cilantro and sliced a serrano chile. Feel free to get creative with your garnishes.
Once the Pozole Verde has been simmering for 10-15 minutes you can serve it up! Add hominy and broth to each bowl and top with your favorite garnishes. Enjoy!!
Store leftovers in an airtight container in the fridge where it will keep for a few days. I usually reheat it on the stove over medium heat -- if it has thickened up simply add a splash of stock or water to thin it out.