In a small bowl, soak saffron strands in warm milk for 5 minutes.

In a mixing bowl, beat softened butter and powdered sugar until light and creamy.

Stir in the chopped pistachios and saffron-infused milk.

Sift together flour, cornstarch, and salt, then fold them into the butter mixture.

Use a spatula or hands to form a soft dough.

Divide the dough into two equal portions, wrap in cling film, and refrigerate for 1-2 hours (or freeze for 30 minutes if short on time).

Roll out one portion of chilled dough on a floured surface to 3mm thickness.

Use a 6 cm round cookie cutter to cut cookies. For half the cookies, cut a 1.5 cm hole in the centre.

Place cookies on a parchment-lined baking sheet, leaving 1-2 inches of space between them.

Freeze for 10-15 minutes while the oven preheats to 180°C (350°F).

Bake for 12-15 minutes until edges turn golden.

Let cookies rest on the baking sheet for 5 minutes, then transfer to a wire rack to cool.

Blend pistachios into a smooth paste.

Beat cream cheese until creamy, then add butter, pistachio paste, powdered sugar, and green food colouring (if using). Mix well.

Transfer to a piping bag and pipe onto the whole cookies.

Gently place the cut-out cookies on top and press lightly.