Place vegetables and chicken broth in a large saucepan. Bring to a boil; reduce heat and cook, covered, until vegetables are tender, about 10 minutes. Mix milk with cornstarch, salt, pepper, and thyme; add to cooked vegetables. Cook, stirring constantly, until soup just begins to boil. Remove from heat; add cheese and stir until melted.
Makes about 4 cups .
This dish is typically served on New Year's Day to bring luck.