Combine beans and boiling water in slow-cooker. Let stand while preparing other ingredients.
Add onion, garlic, jalapeno, cumin and chili powder to pot. Place chicken on top. Quarter squash lengthwise; seed. Cut crosswise into 3/4-inch pieces. Add to pot.
Cover and cook on low heat for 7 hours or until beans are tender. Stir in hominy, sour cream, salt, lime juice and chopped cilantro.
Spoon into bowls. Garnish with sour cream, chopped tomato and cilantro leaves.
Soak beans overnight; rinse and drain. Cook according to package directions; reserve 1 cup cooking liquid; drain beans. Heat 2 tablespoons oil in Dutch oven. Add onion; cook, covered, 10 minutes. Stir in garlic, jalapeno, cumin, chili powder, squash, hominy, beans. Add 1 cup bean liquid. Simmer, covered, 12 minutes. Stir in chicken; cook 10 minutes. Remove from heat. Stir in salt, sour cream, lime juice, cilantro.