Christmas pinwheel cookies

- Beat softened unsalted butter (1 cup or 250g) and granulated sugar (1 cup) together until light and fluffy (around 3 minutes or more).

- Add 1 very large egg and 1 tsp of vanilla extract, then beat until well combined.

- Sift together 3 cups of all purpose flour (plain flour), 1/2 tsp baking soda and 1/2 tsp of salt. Take a spoon and mix all together.

- Add flour mixture to butter & egg mixture and knead.

- Divide dough in half. Wrap one part of it in a plastic wrap and set aside.

- Add 3 tbsp of cocoa powder and 1 tsp of cinnamon to another half...and knead...and knead...until well combined.

- Form cocoa dough, wrap it in a plastic wrap. Put both halves in a fridge for 4-5 hours (preferably overnight).

- Separately roll both halves on a baking parchment (or flour the work surface well to prevent sticking in case that you don't have it). Don't forget to flour the rolling pin as well.

- Put rolled dough layers on top of one another and peel off baking paper from the top layer.

- Trim the edges to get a kind of a rectangle-looking shape (makes slicing easier). Using baking parchment as an aid tightly roll up cocoa and vanilla dough together into a log.

- Wrap the log into a plastic wrap and refrigerate for at least 1 hour.

- Grease two baking sheets with butter and then slice the rolled combined dough into 4 mm/1.6in thick slices. You can use small metal spatula or a sharp knife for slicing but make sure they are dusted with flour to prevent sticking.

- Place cookies onto a baking sheet 2.5cm/1in apart and put them in the oven. Bake for 9 minutes on 150C fan/170C/gas mark 3/338F or until the Christmas cookies are firm to touch. The dough needs to be refrigerated so place it back into the fridge if you're not slicing it.

- When baked leave the Christmas cookies on a baking sheet until cooled down completely.

Store them in an airtight container to stay fresh and to prevent softening.