Heat oil in a dutch oven or large pot over medium-high heat. When oil is hot, carefully place seitan pieces into pot. Sear on all sides till nicely browned, several minutes on each side. Remove from pot and set aside.
Add onion, celery, carrots, parsnips and fennel to the pot. Stir and let cook for several minutes. Add tomato juice, wine, vegetable broth, paprika, thyme, black pepper, 1 teaspoon salt and bay leaf. Bring to a simmer and cook until vegetables are tender, about 10 to 15 minutes. Add seitan and cover pot. Cook for another 3 to 5 minutes, until seitan is hot. Remove seitan from pot and place on a cutting board. Slice into thin strips. Spoon vegetables and broth into bowls and top with sliced seitan. Serve immediately.