1Take your cleaned leeks and slice of the hairy roots at the bottom and discard the roots. Slice into 1/2" medallions going slightly into the green leaves for added color and flavor.
2In a deep skillet, slowly melt your butter until liquid. Add your leeks a handful at a time and saute until leeks are soft and mostly translucent. Sprinkle with salt and pepper and mix thoroughly.
3Slowly add your flour, one tablespoon at a time, mixing until your leeks and flour form a thick pasty mixture. Remove from heat,.
4Pour your beef stock into a 5 quart dutch oven and bring to a boil. Add your potatoes and cook until almost tender. Stir in your cream and bring it to a low boil. Reduce to a simmer and slowly add your leek mixture stirring continuously. Let it simmer on low until the leeks reach your desired level of softness and the soup reaches your desired consistency.
5Serve in bowls with a sprinkle of paprika and sprig of fresh parsley.