If using breadmaker, add wet then dry ingredients and use dough setting.
If using a Kitchenaid, add all ingredients and use a bread hook. Once ingredients form a shaggy dough, allow the machine to knead for 8 minutes. Form kneaded dough into a smooth ball and let rise for 1 hour before continuing
Cut dough into 6 pieces.
Gently flatten each piece into a circle with your fingers. Do not use a rolling pin. Add the filling to the center of the circle and pull up the sides to form a neat ball.
Pinch seams tightly to be certain dough is fully sealed around filling.
Flip over and gently flatten stuffed sandwhich and place onto a cookie sheet lined with parchment.
Combine egg yolk and 1 Tbsp water and brush on each sandwich.