Split the vanilla beans in half, lengthwise, with a pairing knife.
Use the back of a knife to remove the seeds.
Place the seeds and the split beans in a clean half-litre jar or bottle.
With the help of a funnel, pour the liquor over the beans in the jar. Use chopsticks to make sure the vanilla beans are submerged.
Close the jar tightly to seal it and store the jar in a cool, dark place, like a cellar or a cold-storage room or pantry.
Let the vanilla extract infuse for 3 to 6 months.
Notes
Note that after about a year of extraction, the vanilla beans may begin to disintegrate, so you may have to strain the extract to use it.For larger batches, increase the number of beans and alcohol.To test the flavour of your homemade vanilla, mix a drop or two it with a spoonful of whipping cream. Otherwise, you may not be able to appreciate the flavour of the extract and determine if it needs more time.Some avid vanilla extract makers add oak wood blocks to their extract to develop other flavours in the extract. For double fold extract (a more flavourful extract), use 60 grams (2 ounces) vanilla beans per 250 mL (1 cup) of alcohol.