This grilled cheese is a different play on a recipe an accomplished chef is most likely already familiar with. From Melt: 100 Amazing Adventures in Grilled Cheese (page 49)
Preheat oven to 350°F.
In a mixing bowl, combine all croquette ingredients except butter. Form two patties.
In a sauté pan turned to medium heat, cook salmon patties in sweet butter until brown, flipping when necessary. Remove from heat.
In a mixing bowl, combine mayonnaise, dried dill, and lemon zest.
To form sandwich, place 1 croquette on each bottom piece of bread to form two sandwiches, followed by lemon dill mayonnaise to taste, Havarti dill, and top piece of bread.
Bake sandwiches for 5 minutes.
Serve hot with any leftover lemon dill mayonnaise on the side.