Combine water and broth in a large saucepan; bring to a boil. Add cauliflower; return to a boil. Reduce heat and cook 10 minutes or until tender. Remove cauliflower from broth, reserving broth. With knife blade in processor, add cauliflower. Pulse 8 to 10 times or until cauliflower is finely chopped, but not pureed. Combine milk powder, flour, nutmeg, and pepper; add to reserved broth, stirring well with a wire whisk. Add chopped cauliflower and bring to a boil; reduce heat and simmer 15 minutes or until slightly thickened. Ladle soup into 6 individual bowls; garnish with minced parsley if desired. Serve with lemon wedges.