Zupa Kartoflana Recipe from Poland - Delicious Potato Soup

Ingredients

• 3 medium potatoes , sliced
• 2 stalks celery
• 1 large onion , sliced thin
• 2 carrots
• 1 sprig parsley
• 2 qt (1.89 liter) water
• 3 tbsp butter
• 1 tbsp flour
• 1 cup hot milk
• salt and pepper to taste