Preheat oven to 425°F. Line two sheet pans with parchment paper or a silicon baking mat. (you will likely need two baking sheets if you make 12 bundles, about six fit on one half sheet pan).
On a lightly floured surface, roll the puff pastry out into a large rectangle about double the original size. Square off edges and cut into 6 squares. (I use a pizza cutter to do this).
To make the bundles, place slice of ham on top of the square. If necessary, fold the slice of ham in half so that it fits on the square. Follow with 1-2 tablespoons of cheese.
Fold one corner over the ham and cheese, then the opposite corner over. You can dip your finger in a little water and use that as “glue” to seal the corners together. Brush puff pastry with egg wash. Sprinkle with everything bagel seasoning (or use flaky salt and pepper if not using the everything seasoning)
Bake until puff pastry is golden and puffed, about 12-15 minutes. Serve immediately.
Notes
The trick with puff pastry is to let it thaw enough so that it is pliable and easy to work with, but not let it get too warm. I like mine to thaw just enough so that I can roll it out, about 30-40 minutes at room temperature is perfect. If the puff pastry is too warm, it will be difficult to work with, and it won’t puff up as much when baked. If it gets too warm, pop it back in a fridge or freezer for a bit so it can firm up. Remember that it should be pliable but not so soft that it is hard to work with.Leftovers can be stored in a sealed container in the fridge for 2-3 days.