Peel and dice potatoes into 1-inch cubes.
Add potatoes, onion, and garlic to the crockpot.
Pour in broth. Add butter, salt, pepper, and thyme. Stir.
Cover and cook on low for 6–7 hours or high for 3–4 hours until potatoes are tender.
Use a potato masher to mash about half the potatoes in the pot for a creamy texture.
Stir in heavy cream. Cook on low for another 20–30 minutes.
Taste and adjust seasoning.
Ladle into bowls. Top with bacon, cheese, sour cream, and chives. Serve hot.