Split each croissant in half lengthwise. On the top half of each croissant, spread 1 tbsp of honey mustard, and on the bottom half, spread 1½ tbsp of the preserves or marmalade of your choice.
Pile 2-3 slices of turkey on the bottom each croissant. Layer that with 2 slices each of havarti and close each croissant
Place each sandwich on a baking sheet lined with parchment
Meanwhile, in a small bowl, combine butter, garlic, honey, and bagel seasoning.
Brush the top of each croissant liberally with the honey garlic butter.
Bake for 5-8 minutes, or until the cheese is melted and the tops of the croissants are golden brown.
Remove the sandwiches from the oven, open each one up, and stuff with 1/4 cup of arugula. Close the sandwiches and drizzle with a bit more honey if desired.
Serve immediately with additional honey mustard and jam/preserves on the side.