This creamy soup makes an indulgent but not too heavy meal on a hot summer day. Pick the freshest sweet corn you can find.
Cut corn kernels from cobs using a sharp knife. Reserve 1 cup corn kernels. Place remaining corn kernels in a 5- to 6-quart slow cooker. Working over a rimmed pan, use the back of the knife to scrape cobs to release all juices from cobs. Add corn milk, stock, potatoes, yellow onion, thyme sprigs, garlic, salt, and pepper to slow cooker.
Cover and cook on LOW until potatoes are very tender and chowder has thickened slightly, about 6 hours.
Meanwhile, stir together reserved 1 cup corn kernels, bacon, red onion, chives, and lime juice in a small bowl. Chill until ready to serve, up to 6 hours ahead.
Remove half of chowder, and set aside. Process remaining chowder in slow cooker using an immersion blender until smooth. (Or transfer half of chowder to a blender, and remove center piece of blender lid to allow steam to escape. Secure lid; place a clean towel over opening in lid, and process until smooth.) Stir together reserved and pureed chowder in slow cooker. Stir in heavy cream. Divide evenly among 6 bowls; top evenly with fresh corn topping.