Preheat and Prepare: Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper for easy cleanup.
Assemble the Croissants: Slice the croissants in half lengthwise. On the bottom half of each croissant, layer 2 slices of ham and 2 slices of Swiss cheese. Place the top halves back on.
Make the Honey Mustard Glaze: In a small bowl, mix the melted butter, honey, and Dijon mustard until smooth. Brush this glaze generously over the tops of the croissants.
Add the Topping: Sprinkle everything bagel seasoning evenly across the glazed croissants for a savory, textured finish.
Bake to Perfection: Place the assembled croissants on the prepared baking sheet. Bake for 15-17 minutes, or until the croissants are golden brown, and the cheese is melted and bubbly. If they brown too quickly, cover them loosely with foil.
Cool and Serve: Allow the croissants to cool for a few minutes before serving. This lets the cheese set slightly and prevents burns from the hot filling. Enjoy them warm for the best experience!