Using a hand held electric mixer, beat the butter till fluffy. Add the sugar and beat for 2 minute, till smooth. Mix in the vanilla extract, cinnamon and allspice powders. Add the vanilla and beat until combined. Mix the salt and flour together and mix this into the butter-sugar mixture.
Divide this mixture into 4 equal portions. Mix one colour into each portion (yellow, orange, red and green). Flatten each portion into rounds and stack all four, one on top of the other. Divide the stacks into two and roll them into balls, swirling the colours. Don’t work the dough too much or you will not have a distinctly patterned marbling.
Flatten again into rounds, wrap in plastic film and refrigerate at least for an hour. You can leave this for a day or two as well and work on the dough later. If doing this, leave it on the counter for about 20 to 30 minutes before working on it.
Working on one round of dough at a time, roll it out on a lightly floured counter or between two pieces of parchment, until it is 1/4-inch thick. Cut out shapes using leaf shaped cutters.
Transfer to a parchment lined baking sheet. Using a butter knife, create “veins” on the cut out leaves. Refrigerate till firm (about 20 to 30 minutes).
Bake at 170C (325F) for 12 to 18 minutes till the edges of the cookies start turning a golden brown. Watch them as they can burn rather quickly! Cool completely on a wire rack and store in an airtight container.