01 - In a small mixing bowl, gently combine lobster meat, cream cheese, mayonnaise, chives, lemon zest, and a pinch of salt and pepper until uniformly blended.
02 - Arrange bread slices on a clean surface. Evenly spread unsalted butter on one side of each slice.
03 - Distribute half of both Gruyère and cheddar cheeses onto the unbuttered sides of two bread slices.
04 - Spoon the lobster filling evenly over the cheese layers. Top each portion with the remaining shredded cheeses.
05 - Place the remaining bread slices over each sandwich, ensuring the buttered sides face outward.
06 - Preheat a large skillet or griddle over medium heat. Place sandwiches on the surface and cook 3–4 minutes per side, pressing lightly, until bread turns golden and cheese is melted.
07 - Remove sandwiches from the skillet and allow to rest for 1 minute. Slice and serve immediately while hot.