Add the cubed potatoes, diced red bell pepper, frozen sweet corn, diced onion, and minced garlic to the slow cooker.
Pour in the vegetable broth and stir in the dried thyme, salt, and black pepper.
Cover and cook on low for 6 hours until the potatoes are soft.
Use a potato masher to lightly crush some of the potatoes for thickness while leaving chunks intact.
Stir in the heavy cream, then cover and cook on low for 20 more minutes to warm through.