I make posole a lot, both red & green with pork, chicken, and/or beef. My biggest recommendation is to switch from canned to dried hominy - amazing difference in taste and texture. Even easier in the Instant Pot since you can cook the dried hominy in about 15-20 minutes instead of several hours. Amazon carries dried posole/hominy - I buy the 5-pound bag (keeps forever in the pantry) but you might want to start out with a smaller package.
Here's one of my favorite recipes for Green Posole (based on a myrecipes.com recipe). It's written for canned hominy and a slow cooker but easily converts to dried hominy in the Instant Pot...
Creamy Pumpkin Seed and Green Chile Posole
Base:
• 1 large yellow onion, cut into wedges
• 3 large poblano chiles
• 1 serrano chile
• 1 1/2 pounds tomatillos, husks removed, rinsed
• 4-6 unpeeled garlic cloves (or cloves roasted garlic)
• 2 dried ancho chiles, stemmed and seeded
• 1/2 cup salted, roasted pumpkin seeds (pepitas)
• 1 1/2 pounds pulled pork or chicken
• 2 cans (29 oz. each) white hominy, rinsed and drained
• 5 to 6 cups vegetable or chicken broth
• About 5 tsp. dried Mexican oregano, divided
• 1 teaspoon ground cumin
• 1 large zucchini, cut into large dice
• Accompaniments: corn tortillas, cilantro leaves, thinly sliced green onions, and crumbled cotija cheese
Preparation
1. Preheat broiler with oven rack 3 in. from heat. Set yellow onion, poblanos, serrano, tomatillos, and garlic (if raw) on a rimmed baking sheet. Broil, turning, until vegetables are browned to blackened all over, 15 to 30 minutes, moving them to a bowl as browned. Let cool.
2. Toast ancho chiles in a large pot over medium heat until fragrant, pressing down with tongs and turning occasionally, about 3 minutes. Turn off heat.
3. Peel and seed poblanos and serrano. Peel garlic. Whirl serrano, garlic, onion, tomatillos and any juices, and 1/2 cup pumpkin seeds in a food processor until very smooth. Pour into crockpot pot with whole anchos (they'll fall apart as they cook). Coarsely chop poblanos and add.
4. Stir in hominy, meat, 5 cups broth, 2 tsp. oregano, and the cumin. Cook at Low heat for 6-8 hours. Discard any large pieces of ancho chile.
5. Stir zucchini into posole about 30 minutes before serving. Stir in more broth if you'd like a thinner soup.
6. Ladle into bowls and serve with oregano and other accompaniments to taste.
