Steam the sweet potatoes for about 20 min until cooked.
Let them cool slightly and mash the flesh.
Add the finely chopped onion, along with all the fresh and dry herbs, including the mustard, breadcrumbs, and cheese, season with salt and pepper, and mix everything well together.
Roll out the puff pastry.
Place the strip of puff pastry widthwise in front of you.
Lightly brush a band of about 1 cm with egg wash, spread the potato filling as evenly as possible, avoiding the brushed part of the dough, and carefully roll from the bottom to the top.
Leave the seam at the bottom of the rolled roll.
Let it chill in the refrigerator for at least 1 hour, lightly brush with egg wash, and roll the puff pastry log through the mixture of poppy seeds and Parmesan.
Cut into pieces of 1.5 cm, lay them flat on a baking sheet lined with parchment paper, and bake well for 15-20 min at 175-180 ยฐC.
Serve warm.
You can also make these in advance, store them in the refrigerator, and reheat them in the oven at 180ยฐC for about 4 min.
Tips
No extra tips needed, Just Enjoy!