In a large pot over medium-high heat, add 1 teaspoon of oil and saute the chopped onion, garlic, and celery. Stirring occasionally, until translucent ( about 4 minutes).
Proceed to add chicken or vegetable broth (low sodium), peel chop potatoes, salt and bring to a boil. Reduce the heat and simmer, covered, until the potatoes are tender, 15 to 20 minutes.
Remove the potatoes from the stove, and carefully puree them (including all liquids) in an immersion blender or food processor.
Return the creamy puree back into the pan and over low heat, add the cheese and stir until melted. Remove the pan from the heat. Taste the soup and add more salt if needed. Serve the soup topped with bacon and chives.