Add the cubed potatoes to a large pot and cover with cold water. Bring to a boil and cook for 15-20 minutes or until the potatoes are fork-tender. Drain potatoes.

Heat another large soup pot over medium heat. Once hot, add bacon and cook for 5-7 minutes or until crispy. Remove the cooked bacon, reserving two tablespoons of the bacon fat in the pot.

Add the diced onion to the bacon fat and sauté for 4-5 minutes, then add the minced garlic and sauté for another minute.

Add the butter and stir until melted, then whisk in the flour. Cook for about 2-3 minutes, stirring frequently.

Whisk in the chicken broth and bring it to a simmer, stirring often as the broth thickens.

Add two cups of the cooked potatoes and two cups of the broth into a blender and blend until completely smooth. Pour back into the pot along with the remaining cooked potatoes and stir. Reduce the heat to medium-low.

Add the heavy cream, shredded cheddar, sour cream, salt, pepper, and ½ of the cooked bacon. Stir and let simmer for 10 minutes before serving.

Ladle the soup into bowls and garnish with the remaining cooked bacon, more shredded cheddar, and chopped green onions.