1/2 cup sugar
1/4 cup water
1/2 cup vodka
2 teaspoons vanilla extract
In a saucepan, combine sugar and water. Bring the mixture to a boil, then reduce the heat to low and let simmer 5 minutes. Remove from heat and cool to room temperature.
Pour vodka and vanilla extract into the room temperature mixture. Pour the liquor into a sealable decanter; seal and store for at least two weeks before serving.