Add the rice and remaining stock to the pot, and stir until it is fully incorporated into the tomato mixture. Transfer the entire pot, including the lid, to the oven. Bake 25-30 minutes, until the rice is uniformly cooked (once the grain expands). The liquid does not need to be fully absorbed for the rice to be ready. You can cook this longer, depending on how soupy (or a la chorrera) you like it. The liquid continues to evaporate with the residual heat, so take it out of the oven when it is a little soupier than you want.