Stir in soy sauce and ponzu. Discard kombu. Working in two batches, carefully ladle soup into a blender and purée until smooth. Return soup to pot. Season with salt and pepper. Make the croutons ...

Add tofu; cook until browned (2-5 minutes). Add garlic and ginger and cook about 2 minutes. Add mushrooms, broth and cabbage and simmer 5 minutes. Stir in reserved noodles. Add soy sauce. Ladle soup ...