In a large mixing bowl or the bowl of a stand mixer, add butter and sugar and mix on high speed until fluffy and well-combined. Mix in the rosewater.

In a separate bowl, stir together flour, rose petals, and salt.

Add dry ingredients to the butter and sugar mixture, and mix on low until it resembles coarse breadcrumbs.

Use your hands to bring the mixture together, kneading gently until a loose dough forms.

Shape into a log, approximately 8 inches long and about 1 1/2 inches in diameter.

Roll in Demerara sugar.

Wrap log in clingfilm/plastic wrap and chill in the refrigerator until firm, at least 30 minutes.

While dough chills, preheat oven to 180° C / 355° F. Line a baking tray with parchment or a silicone mat, and set aside until ready to use.

Unwrap log. With a sharp chef’s knife, slice into slices, each about 1/4 inch thick.

Arrange on prepared tray.

Freeze cookies on tray for 10 minutes. (Alternately, you can chill the slices between squares of parchment, if your tray does not fit in the freezer.)

Bake in preheated oven until shortbread is lightly golden around the edges, about 13-15 minutes. (If using two trays, bake one at a time.)

Remove from oven and transfer to a wire rack to cool.

Store shortbread cookies in an airtight container at room temperature for up to five days.