Put chocolate and heavy cream in a 2 or 2 and ½ quart crock pot (slow cooker).
Stir together to combine.
Cover and cook on low setting for 1½ to 2 hours, stirring once or twice while cooking.
Whisk until smooth. Top with graham cracker crumbs. You can leave chocolate in crock pot on warm setting, covered, or transfer to a heatproof bowl if it will be served immediately (while still warm).
If leaving in crock pot, stir occasionally.
Serve fondue with dippers of your choice. I used strawberries, marshmallows, and graham crackers. Sliced bananas or animal crackers would also work well.
Recipe by Wishes and Dishes at https://wishesndishes.com/crock-pot-smores-fondue/