1. **Prep the Bread:** If desired, cut the crusts off the bread slices for a neater square shape (and to make them extra kid-friendly).

2. **Assemble:** Place cheese slices between two pieces of bread to form sandwiches. You want the cheese to stay inside the bread, so tear the cheese slices to fit if necessary.

3. **Butter:** Spread a thin, even layer of softened butter on the outside of each sandwich (top and bottom bread slices).

4. **Grill:** Heat a large non-stick skillet or griddle over medium heat. Place the sandwiches in the pan and cook for 2-3 minutes per side, or until the bread is golden brown and the cheese is fully melted.

5. **Cut into Minis:** Remove the sandwiches from the pan to a cutting board. Let them cool for about 1 minute (to keep the cheese from oozing out too much). Using a sharp knife, cut each sandwich into 4 small squares or triangles.

6. **Serve:** Arrange the mini grilled cheeses on a platter and serve immediately while warm. Pair with small cups of tomato soup for the ultimate dipping experience.