How to make
To make the pineapple marmalade, drain the pineapples ahead of time, blend them in a blender, drain any excess liquid and put them to boil in a wok, until absolutely all of the liquid evaporates.
Add the sugar and boil until the marmalade darkens and gets sticky, stirring nonstop. Finally mix with the corn starch. Put the prepared marmalade in the fridge.
For the dough, beat the butter and sugar in a bowl, next add the egg, beat until homogenized. Sift the flour and powdered dry milk and while stirring nonstop pour the liquid mixture into the dry ingredients. Form a smooth and stretchy dough and add a little more flour if needed - the dough must not be crumbly.
Scoop teaspoonfuls of the pineapple marmalade and form balls in your palms.
Place each ball of marmalade onto a a flat piece of dough, rolled out to about 1 1/2″ (4 cm) in diameter, and cover, forming slightly elongated fritters. Arrange them in an oven dish with baking paper, carefully make a grid onto each fritter and smear with beaten egg yolk.
Bake them in a preheated 350°F (175 °C) oven for about 20 min. or until they turn golden brown.