Beat the room-temperature butter with the sugar using a mixer, add the egg, and mix.

Add the baking powder, salt, and vanilla essence, mix, then add a cup of flour. Work in the rest of the flour gradually by hand and knead the dough.

Roll the dough into a thin sheet no thicker than 0.5 cm and cut out shapes: an equal number of whole rounds and rounds with a pattern cut out of the center.

Place on a baking sheet and bake at 180°C for 12-15 minutes. Remove and let cool.

Spread the whole rounds with melted chocolate and cover with the windowed rounds.

Let the cookies sit until the chocolate sets. Enjoy!