Preheat oven to 375 degrees F. Line a large sheet pan with parchment paper or foil.
Slice croissants in half lengthwise. Place 2 cheese slices on bottom, followed by ham slices, and additional cheese on top. Place the croissants on sheet pan.
In a small bowl, mix melted butter, honey, Dijon, brown sugar and poppy seeds. Brush on top of the croissants. Bake for 7-9 minutes, or until cheese is melted.