What type of cheese is used in the croissant sandwich?

The croissant sandwich typically features Gruyere cheese due to its distinctive qualities that complement the flaky, buttery texture of the croissant. Gruyere is a semi-hard Swiss cheese known for its rich, nutty flavor and excellent melting properties, making it a popular choice for sandwiches. Its creamy consistency enhances the overall eating experience by adding depth to the flavors without overwhelming the other ingredients in the sandwich.

In contrast, the other cheeses mentioned may not provide the same balance or flavor profile suitable for a croissant sandwich. Cheddar cheese can be quite sharp and may overpower the delicate taste of the croissant. Feta cheese, while flavorful, has a crumbly texture that wouldn't meld well in the sandwich, and blue cheese often has a strong and pungent flavor that may not suit the lighter notes of the croissant. Thus, Gruyere cheese is the ideal option for enhancing the sandwich while maintaining harmony among its components.