There is a lot of recipes for making vanilla extract online that simply require dropping vanilla pods into a bottle of vodka and then waiting an extensive period of time for the vanilla flavour to permeate into the vodka.
If you however would like a much quicker method that will also greatly increase the vanilla flavour of your vanilla extract, we have developed the following simple vanilla extract recipe through several years of experimentation.
Chop vanilla pods into small pieces and then boil the cut vanilla pieces in a covered pot in a fluid made from equal portions of vodka and water for 5 minutes at a ratio of 100g (3.5oz) of vanilla pods per one litre (33fl.oz) of fluid. Let soak over night and when cool strain out the vanilla pieces with a very fine sieve. Sugar can then be added to taste. We suggest around 40g (1.5oz) of sugar per one litre (33fl.oz). The cut vanilla pieces can then be dried and ground using a coffee grinder for use as vanilla powder.
Note that the optimum alcohol continent is suggested to be between 15% and 20%. At this level the alcohol still provides the preservative affect but does not overpower the vanilla flavour. By using equal portions of vodka and water the normally 35% alcohol volume of the vodka is reduced to 17.5%.
The alcohol content contained in the vanilla extract will ensure it keeps indefinitely. Use 15ml (0.5fl.oz) which is about 3 teaspoons per one litre (33fl.oz) during food preparation.