For the bacon, I just cut a package in half, chopped that and fried until good and crispy in a small pan. Add the bacon to your slow cooker, just set the pan aside as you will use that in about 6 hours or so.

Bacon and onion added to the slow cooker.

Add the 3 cups chicken stock, and potatoes to your slow cooker and stir to combine. Cook on Low setting for 6-8 hours or on High setting for 3-4 hours, or until the potatoes are completely tender and cooked through. Once cooked, chop and fry up the other half package of bacon and add that to slow cooker and stir to combine. (Photo shows right when the slow cooker was started.)

Once the soup has slow cooked and is about ready to serve, heat the bacon fat, or butter, in the same pan used as the crisping the bacon, on the stove over medium-high heat until it has melted. Whisk in the flour until it is completely combined, and then cook for 1 minute, stirring occasionally. Gradually add in the evaporated milk while whisking it together with the flour mixture, and continue whisking until the mixture is completely smooth. Let the mixture continue cooking until it reaches a simmer, stirring occasionally, and then it should get really thick.

Immediately pour the milk mixture into the slow cooker with the potatoes, and stir until combined. Add in the cheddar cheese, Greek yogurt (or sour cream), salt and pepper, and stir until combined. If you would like the soup to be even thicker, you can use a potato masher or a large spoon to mash about half of the potatoes (while the soup is still in the slow cooker) to thicken the soup up. If you would like the soup to be thinner, add in an extra 1-2 cups of warmed chicken or vegetable stock. Stir to combine, then taste and add more salt and pepper if needed.

Serve as is or with cheese, sliced spring onions, cooked bacon, sour cream, etc.