In a large saucepan over medium heat, add the chopped bacon, cook while stirring for about 4-6 minutes, until crispy. Add marjoram and cook for an additional minute, transfer the bacon and marjoram to a plate.
Add the onion and garlic to the buttered pan and cook, while stirring for an extra 3-4 minutes. Add the potatoes and cook, while stirring for an additional 3-5 minutes.
Add the chicken stock and water, bring to a boil, cook for 15-20 minutes or until tender. Remove a cup of potatoes and set aside. To the saucepan, add the cheese, stir until melted, add the sour cream and milk simmer on low for 2-4 minutes.
Mash or blend with a stick blender the cup of potatoes, add them back to the pan as a thickener. Remove from heat serve and top with bacon, chives and sour cream. Add salt and pepper to taste.
For added flavor lay a sprig of marjoram in the bowl (with the stem at the edge of the bowl) before ladling the soup into the bowl.