Lets face it, this is one of the greatest combinations ever invented!
For the soup, use this recipe.
For the sandwich, you can use just about any type of cheese. I made mine with parmesan, mozzarella, Gruyère, and basil. I normally put mustard in my grilled cheese, but the tomato soup has plenty of acidity. There’s a secret to making awesome grilled cheese. My secret move is to put the parmesan on the outside of the bread. You need a non-stick pan or even better a Panini press for this to work though. As the bread toasts, the parmesan releases its oil into the bread making the parmesan crispy and the bread more flavorful. If you’ve ever had a parmesan crisp, imagine making the outside of your bread taste like that.