Blanch tripe in boiling water 5 minutes, then drain and rinse.
Place tripe in a large pot, cover with fresh water, and simmer covered 1 hour 30 minutes until tender.
Drain, cool slightly, and slice into thin strips.
Melt butter in a large pot over medium heat. Add carrots, celery root, parsnip, and onion, cooking 8–10 minutes until softened.
Add broth, sliced tripe, marjoram, nutmeg, ginger, and cayenne if using.
Simmer 30–40 minutes, uncovered toward the end, until thickened to a hearty stew consistency.
Season with salt and pepper and serve hot.