Combine the stock, bell peppers, corn, rice and thyme in a saucepan. Bring to a boil, lower the heat, cover and simmer until the rice is tender, about 5 minutes. Set aside.
Preheat the oven to 400 degrees. Wash (but do not dry) the kale and trim and discard the stems. Place the kale in a large pt, cover and cook over medium-high heat until it wilts, about 5 minutes. (The water on the leaves is sufficient to steam the greens.) Drain and coarsely chop. Fluff the rice mixture with a fork.
In a large bowl, combine the cooked kale, the rice mixture, ricotta, half of the Parmesan, salt and pepper. Place in an oiled, 2-quart gratin dish. Sprinkle with the remaining Parmesan, breadcrumbs and wheat germ. Bake until golden and bubbling almost 30 minutes.