1 1/2 cup unsalted butter, softened
1 cup sugar
1 large egg
2 teaspoons vanilla extract
4 1/2 cups all-purpose flour
1/2 teaspoons salt
In a bowl, with mixer on medium, beat butter and sugar until fluffy; beat in egg and vanilla extract. On low, beat in flour and salt.
Divide dough in half; shape each half into a 1/2-inch-thick disk. Wrap in plastic wrap; chill until firm.
Heat oven to 175 degrees Celsius, ( 350 degrees F).
On floured surface, roll dough, 3 mm (1/8-inch) thick; cut into shapes. Transfer to ungreased baking sheet(s). Bake until lightly golden around the edges, 10 minutes. Let cool 5 minutes on sheets; transfer to racks to cool. Decorate as desired; store in an airtight container up to 2 weeks, or freeze, undecorated, up to 3 months.
2 large egg whites, or more to thin icing
4 cups sifted confectioners' sugar, or more to thicken icing
Juice of 1 lemonMakes about 2 1/2 cups
Food coloring of your choice
To make the icing, whisk the egg whites and add the confectioner sugar, pass lemon juice through a fine sieve, to remove any pips or bits. Mix the icing sugar with the lemon juice, (if too thin add more confectioners sugar, if too thick add a little water till you have the consistency you want) Mix the ingredients and divide into different bowls and add the color you like to each bowl. Mix and pour the icing into bags for decorating your cakes.
Decorate the cakes with the icing and leave to dry and harden. Takes 12 hours or more.