1. Sort and wash beans; place in a large Dutch oven. Cover with water to 2 inches above beans; bring to a boil. Cook 2 minutes; remove from heat. Cover and let stand 1 hour. Drain beans.
2. Place beans in a 3-quart electric slow cooker. Stir in chicken broth and next 4 ingredients (through garlic). Cover and cook on LOW for 10 hours or until beans are tender.
3. Stir in lime juice. Mash bean mixture with a potato masher until slightly thick. Sprinkle with queso fresco, cilantro, and pumpkinseed kernels.