Cream butter and sugar until pale and fluffy.

Beat in egg and vanilla until smooth.

Add flour and salt and mix just until a soft dough forms.

Wrap dough in plastic wrap and refrigerate for 30 minutes. This helps keep shapes crisp.

Preheat oven to 350°F (175°C).

Roll dough on a lightly floured surface to ¼-inch thickness.

Cut into stars, hearts, or classic rounds.

Brush lightly with egg wash and sprinkle with pearl sugar or almonds.

Bake 8–10 minutes, just until edges turn lightly golden.

Do not overbake — Butterplätzchen should stay pale.

Cool on baking sheets for 5 minutes, then transfer to a rack.