In a large saucepan, heat the olive oil over medium-high heat. Add the chorizo, carrots, celery and garlic and cook until the vegetables are slightly softened, about 5 minutes. Add the cumin and cook, stirring occasionally, for 3 minutes. Stir in the chicken broth and hominy and simmer for 20 minutes or until the vegetables are tender. Top with the cilantro and serve with the tortillas.