Cut the eggplant lengthwise into strips and place on the bottom of a casserole dish.
Spoon a layer of tomato sauce onto the eggplant. Now add a layer of uncooked penne on top of the tomato sauce, arranging the noodles in an orderly fashion. Now pour in the vegetable stock, followed by a layer of tomato slices (half of your total amount) and finally, all of the cream cheese.
Place the remaining eggplant on top of the cream cheese, and season with salt and pepper. Now add the rest of the tomato sauce, followed by one last layer of tomato slices and finally, a generous portion of shredded mozzarella.