Preheat the oven to 375°F (190°C).
Cook the rice until tender according to the package directions.
Meanwhile, heat the olive oil in a large frying pan over medium heat. Add the onions and cook, stirring occasionally, until soft and translucent, 3 to 4 minutes. Add the cabbage and cook, stirring occasionally, until it has softened and just starts to turn golden brown, 10 to 12 minutes. Remove from the heat.
Stir in the cooked rice to combine. Season with salt and pepper. Transfer the mixture to a lightly oiled 13 × 9-inch (3.5 L) baking dish.
In a medium bowl, whisk together the tomato soup and cream. Pour the creamy tomato soup evenly over the rice mixture.
Bake until the mixture bubbles and is golden brown on top, 35 to 40 minutes.