Cut the bacon into bite-sized pieces. Heat a dutch oven on medium heat. Once hot, spray the pan with nonstick cooking spray then add the bacon pieces. Cook the bacon on both sides until crispy.Transfer to a paper towel-lined plate and set aside. Drain most of the excess grease from the pan.
Add potatoes, carrots, and celery. Stir and cook for a couple of minutes. Add the garlic and cook until fragrant. Add the broth, parsley, salt, and pepper. Stir and bring the mixture to a boil. Cook until the vegetables are tender.
Once the vegetables are tender, reduce the heat to a simmer. Add milk and heavy cream.Use an immersion blender (masher or blender) to carefully puree about half of the mixture. Simmer for 10-15 minutes to allow the soup to thicken.
Serve soup with crispy bacon, shredded cheddar cheese, and chives.
Store leftovers in an airtight container in the refrigerator for up to 4 days.