This is such a simple thing to do and yet makes the world of difference to your baking.
You can add vanilla sugar to anything, and if a recipe specifically asks for it then using regular sugar will effect the results.
A lot of people will just tell you to store the vanilla pods in the sugar but a much more effective way to get all the flavour out of the vanilla pods is to ground them up.
If you have a coffee grinder this works best but if not a food processor (or pestle and mortar) will work too. A cute mason jar full of vanilla sugar also makes a great gift!
This recipe is from Jamie Oliver.
1lb fine vegan sugar
2 vanilla pods*
Using a coffee grinder or food processor grind the vanilla pods, you may need to scrape down the sides a couple of times.
Add ground vanilla pods and sugar to a food processor and pulse until mixed thoroughly - the mixture will look like an ash colour.
Store in an air tight container.
*NB A fresh vanilla pods will be soft and pungent, if it's not as fresh it will be hard.