Melt butter in dutch oven and add sliced onions, cook gently. Do not let onions brown. Add the potatoes and pepper to taste. Pour in the milk and chicken broth. Cover and cook gently for twenty minutes til potatoes are very tender. Using slotted spoon remove potato and onion to blender and puree. Return to pan and add the half and half. Reheat soup (do not boi). Ladle to bowl and top with bacon and parsley.