Combine the Base: In the basin of a large slow cooker (6-quart or larger), add the diced potatoes, chopped onion, celery, minced garlic, and frozen corn.
Season and Add Liquid: Sprinkle the dried thyme, smoked paprika, salt, and black pepper over the vegetables. Pour in the chicken broth and stir thoroughly to combine all the ingredients.
Slow Cook: Cover with the lid and cook on LOW for 6 to 8 hours, or on HIGH for 3 to 4 hours. The chowder is ready for the next step when the potatoes are completely fork-tender.
Thicken: About 20-30 minutes before you are ready to serve, remove the lid. (Optional: Use a potato masher to briefly mash some of the potatoes right in the pot to naturally thicken the soup).
Add the Cream: Whisk the cornstarch and cold water together in a small bowl until smooth. Pour the slurry and the heavy whipping cream into the slow cooker. Stir well. Leave the slow cooker uncovered on HIGH for the last 20 minutes to allow the broth to thicken and bubble slightly.
Serve: Taste and adjust seasoning with additional salt and pepper if necessary. Ladle the hot chowder into bowls and top generously with crumbled bacon, fresh chives, and shredded cheese.