Heat a large dutch oven over medium heat.
Place the bacon slices flat in the pot and cook, turning a couple times, until crispy and most of the fat had released from the bacon. Using tongs, transfer the bacon to a paper towel-lined plate. Set aside.
Add the onions, salt, and pepper to the dutch oven and cook, stirring occasionally, until the onions are soft and translucent; about ten minutes.
Stir in the potatoes, cauliflower, and stock. Increase the heat to high and let come to a boil.
Reduce to a bubbly simmer and cook, stirring occasionally, until the potatoes are very soft; about 15-20 minutes.
While the soup simmers, chop or tear the bacon into bite-size pieces and set aside.
Using a blender in batches, or immersion blender, puree the soup until all chunks disappear. Taste and adjust seasoning if necessary.
Serve topped with bacon, sour cream, chives, and cheese. Enjoy!