You're allowed to top-off with more liquor as your extract begins to run dry. It practically keeps giving! And you should periodically replenish the vanilla with scraped pods as you cook things that require a vanilla bean. It's like a vanilla bean compost bin.
I ran across the idea of homemade vanilla extract while reading the fantastical "You Asked The Food Lab 164 Questions. Here Are 164 Answers." J. Kenji Lopez-Alt lists it as one of the five things you should make yourself.
Curiously, his recipe says 1 bean in 1 1/2 cups of vodka for 1 week. Nice and easy. Then I looked up other recipes, and they tend to say something like 3 beans in 1 cup vodka/rum for 2 months. Huge discrepancy! In the end, I went with what seemed the more potent recipe (although with only 1 bean because those things are expensive). I'm still working through the store-bought vanilla in my pantry anyway so why not wait.
I'll let you know how it turns out. Stay tuned...
- 1 whole vanilla bean
- 1 cup rum*
- * Rum is more interesting, but you can use vodka if you prefer.
Split the vanilla pod open lengthwise. Add to a jar of rum. The bean should be completely submerged in the rum. Close tightly, shake, and place it in a cool, dark place for two months before using.
Shake every so often for good measure and replenish with rum and scraped vanilla pods as occasion dictates.