Prepare the pastry: In a large bowl, combine the flour, salt, powdered sugar, and baking powder. Add the cold, cubed butter and rub it into the dry ingredients with your fingertips until the mixture resembles coarse crumbs.
Add the eggs and gently knead until a dough forms. Divide the dough into two portions, setting aside one-third for the mummy bandages. Shape both portions into discs, wrap them in plastic wrap, and refrigerate for 1 hour.
Preheat the oven to 340°F (170°C) using the convection setting. Line a large baking sheet with parchment paper.
Prepare the filling: In a medium bowl, whisk together the pumpkin purée, brown sugar, sweetened condensed milk, egg, cloves, cinnamon, and nutmeg until well combined. Set aside.
Once the dough has chilled, place the larger portion between two lightly floured sheets of parchment paper. Roll it out to approximately ⅝ inch (1.5 cm) thick, adding a little more flour if the dough becomes sticky.
Cut the dough into rectangles measuring approximately 2¾ × 2 inches (7 × 5 cm). Arrange them on the prepared baking sheet.
Spread the pumpkin filling evenly over the pastry rectangles. Gather any leftover pastry scraps and combine them with the reserved dough. Roll out the dough and cut it into narrow strips for the mummy bandages.
Cut the remaining dough into narrow strips and arrange them across the tartlets to resemble mummy bandages, leaving a small opening for the eyes.
Brush the pastry with the beaten egg yolk and sprinkle with a little granulated sugar and cinnamon.
Bake for approximately 40 minutes, or until the pastry is golden brown and cooked through and the pumpkin filling is set. Remove from the oven and let cool completely before decorating.
Once cooled, decorate with small eyes made from white and black fondant to complete the mummy faces.