Use white part of leek. Wash well and chop into fine pieces.
Wash and trim squash and chop into medium pieces.
Heat oil in skillet over medium heat. Add leek and saute until translucent.
Add squash and saute, stirring until soft, about 10 minutes. Season with salt and pepper.
Add stock and marjoram, heat to boiling, cover, reduce heat and boil gently for 30 minutes.
Add artichoke puree and mix well.
Pour soup(careful!) into processor/blender and process into coarse puree.
Serve hot with cheese on top.
NOTE: Artichoke puree is available in specialty stores or you can make your own! Drain a can/jar of water-packed baby chokes and grind them in processor/blender. Leftovers can be used in pasta sauce or as a dip for raw veggies.