In large pot, add olive oil, garlic, and onion. Saute for 1 minute. Add sausage. Saute, gently stirring for another couple minutes. Add celery heart and combine. Saute for another few minutes. Add tomato puree and 3 1/2 cups of stock. Season with salt and pepper. Add oregano and parsley stalks.
Mix the mashed potatoes with the remaining chicken stock and add to the soup. Simmer 20 minutes, uncovered. Add white wine and bring back to boil. Pour boiling soup into warmed soup bowls and immediately crack one egg into each bowl. Season with a dash of nutmeg. Serve immediately.