Step 1

Add the potatoes, the onions, the chicken broth, the salt, and the pepper to a slow cooker.

Step 2

Cover and cook until the potatoes are tender, about 6 hours on low or 4 hours on high.

Step 3

In a saucepan, over medium-low heat, combine the butter, the flour, the heavy cream, and the sour cream and whisk until thickened, about 3 minutes.

Step 4

Pour the cream mixture into the slow cooker and stir to combine.

Step 5

Cook the soup on low until the flavors meld together, about 30 minutes.

Step 6

Top with the cheese, the bacon, and the scallions.

Step 7

Serve.