Add 100 g butter and 40 g icing sugar to a mixing bowl, then whisk until smooth and combined.

Add 130 g all-purpose flour to the butter mixture, then fold with a rubber spatula until a soft dough forms.

Add 1 to 2 tablespoons milk only if needed, then gently mix until the dough comes together without being sticky.

Place the dough between two sheets of parchment paper, then roll it to about 5 mm thick.

Transfer the rolled dough to the refrigerator, then chill for 60 minutes until firm.

Preheat the oven to 180°C, then line a baking sheet with parchment paper.

Cut the chilled dough into heart shapes, then place the cookies slightly apart on the lined baking sheet.

Bake the heart cookies at 180°C for 8 to 10 minutes, then remove them when the edges are lightly golden.

Transfer the cookies to a wire rack, then let them cool completely until crisp.

Drizzle or dip the cooled cookies with melted chocolate, then let the chocolate set before serving.