Preheat your oven to 350°F (175°C) to lightly toast the croissants. Only if you are planning to toast them. You can also serve them as cold sandwiches.

Slice the croissants in half horizontally, creating a top and bottom half for each sandwich.

Spread a generous layer of unsalted butter on the cut sides of the bottom croissant half.

Place a few slices of havarti cheese on the bottom half of each croissant.

Layer smoked salmon slices on top of the cheese.

Bring the top and bottom halves of the croissants together to assemble your sandwiches. Gently press to secure the layers.

(Optional) Place the assembled sandwiches on a baking sheet and toast them in the preheated oven for about 5-7 minutes or until the croissants turn golden and the cheese starts to melt.

Serve and enjoy!