Sift the rice flour and corn starch into a mixer bowl and add the cold butter cut into cubes.

Work everything quickly until you obtain a sandy mixture.

Then add the icing sugar, the egg yolks, a teaspoon of vanilla extract and a pinch of salt, and continue to mix the ingredients.

Turn the mixture obtained onto the work surface, sprinkled with rice flour, knead again with your hands and form a smooth and homogeneous loaf.

Wrap it with a sheet of cling film and let it rest in the fridge for at least 1 hour.

Once the time has passed, roll out the pastry between two sheets of baking paper to about 6mm thick and, using Christmas-themed cookie cutters, cut out the biscuits.

Arrange the cookies with all the parchment paper on a baking tray and place on the middle rack in the oven, in static mode at 340°F/170°C, for 10-12 minutes.

Once cooked, take the biscuits out of the oven and let them cool for 5 minutes; then place them on a wire rack and let them cool completely.

Prepare the royal icing: beat the egg whites with an electric whisk, then add the sifted icing sugar, one spoonful at a time, and continue to whip the ingredients at high speed.

Finish with the lemon juice and work briefly again with the whisks until you obtain a thick and frothy icing. Then divide it into three bowls and add a few drops of green food coloring to one and a few drops of red food coloring to the other. Mix well with a spoon until you get the desired shade.

Distribute the white, red and green royal icing in three different piping bags with a small smooth nozzle and decorate the Christmas cookies; then, place them on a rack and let them dry perfectly for about 2 hours.