01 - Pour tomato soup into a medium saucepan and heat over medium, stirring occasionally until hot throughout.
02 - Spread softened butter evenly on one side of each slice of bread. Place a slice of cheddar between two slices of bread, buttered sides facing outward.
03 - Heat a large skillet over medium heat. Add the sandwiches and cook for 3–4 minutes per side until golden brown and cheese is melted.
04 - Ladle tomato soup into bowls and serve immediately with grilled cheese sandwiches.