Plum Butter Pockets
Peel the potatoes and rinse. Cook in a pot of boiling salted water for about 25 minutes. Drain and press through a ricer into a bowl. Let cool.
Mix 50 grams (approximately 3.5 tablespoons) of butter with the flour, semolina, zest, egg yolks, and 1 pinch of salt. Add to the potatoes and knead to a smooth dough.
Roll out on a slightly floured surface to 4 mm (approximately 1/8 inch) thin. Cut out circles to about 10 cm (approximately 4 inches) in diameter.
Mix the plum butter, vanilla seeds, rum, and cinnamon. Place in the center of each cookie. Mix the egg with 1 tablespoon of water and brush the egg wash around the edge of the cookie. Fold the cookies in half and press the edges.
Bring a large pot of salted water to a boil. Turn down the heat and boil the pockets for 4-5 minutes, until they rise to the surface. Remove from the water and drain.
Heat the remaining butter in a pan and cook the breadcrumbs until golden brown. Carefully toss the pockets in the breadcrumbs. Serve dusted with powdered sugar.