Boil potatoes just until tender. ... until smooth and thick. Add potatoes, leeks, and ... thoroughly heated. If soup is too thick, you may add milk to thin.
Preheat oven to 350 degrees. ... carrots about 1/2-inch thick. Chop onion and add. Add mushroom soup and milk and mix well. Place steak and potato mixture in large pan and cook about 1 hour.