Because everything is better with bacon!
After slicing leeks, place in a bowl of cold water and swish around a few times to remove any sand. Heat butter in a large stockpot. Add bacon and fry intil crisp. Remove bacon. Add leeks and saute for about 10 minutes. Then add potatoes and cook for about 5 minutes. Add broth, thyme, bay leaf and chicken broth and bring to a boil. Cover and reduce heat to a simmer. Allow to cook for about 30 minutes. Remove bay leaf. Blend soup in batches and place back in pan. Stir in heavy cream and season with salt and pepper. [If soup is too thick, add a little water.] Garnish with crumbled bacon.