Heat the oil to a large stock pot over medium high heat. Add the chorizo and cook until browned, 3-5 minutes. Use a slotted spoon to transfer the sausage to a plate.
Reduce heat to medium and whisk in the flour to form a paste. Cook, stirring constantly, until the mixture reduces and turns a deep caramel color, 15-20 minutes.
Add the celery, onion, carrot, pepper, and jalapeno; cook until beginning to soften, about 8 minutes.
Add the vegetable stock, tomatoes, rice, and Cajun seasoning. Bring to a boil, then reduce heat and simmer 20 minutes or until the rice is cooked.
Stir in the beans and corn and simmer 5-10 minutes, or until heated through.