Cream the butter and sugar together until light and fluffy
Add the egg and vanilla, mixing until smooth
Sift in the flour and salt, then mix to form a soft dough
Transfer the dough into a piping bag fitted with a star tip (or use a cookie press)
Pipe small flower-shaped cookies onto a lined baking sheet
Add a small dot of jam to the center of each cookie
Chill the cookies in the fridge for 15–20 minutes so they keep their shape
Bake at 350°F (175°C) for 10–12 minutes, or until the edges are lightly golden
Cool completely before packaging or serving
