Preheat your oven to 180°C (350°F) and line two baking trays with greaseproof paper.

In a stand mixer, combine softened dairy-free butter, icing sugar, plain flour, and vanilla extract. Mix on medium speed until a soft dough forms, about 3–5 minutes.

Transfer the dough to a piping bag fitted with a star tip nozzle and pipe rosettes about 2 inches apart on the prepared trays.

Bake the cookies for 10-15 minutes or until lightly golden around the edges.

For the buttercream, beat dairy-free butter until creamy, then gradually mix in icing sugar and vanilla. Adjust consistency with dairy-free milk if necessary.

Spread raspberry jam on one cookie and pipe a dollop of buttercream on another, sandwiching them together.

Dust with icing sugar before serving.