Heat oil in large nonaluminum saucepan or Dutch oven over medium-high heat. Add onion; reduce heat to medium; sauté 5 minutes or until onion is slightly softened. Add potato and fennel seeds; cook, stirring, for 2 minutes.
Add the tomatoes, chicken broth, half the corn and the thyme. Bring to boiling. Reduce the heat to medium-low; simmer, stirring occasionally, for 20 minutes. Season with salt and pepper.
Puree in food processor or blender, working in batches if necessary. Return to pot.
Stir in the cream, the remaining corn and the imitation crabmeat. Gently reheat the soup; do not let boil. Stir in the hot-pepper sauce to taste. Serve the soup warm. Makes 6 servings.