A simple, quick, and inexpensive homemade Kahlua recipe. It's tried and tested, yielding about 2.38 quarts (2.25 L) or about three 25.3 fl. oz. (750 ml) bottles of coffee liqueur with a shelf life of up to one year. Enjoy it poured over ice, to make cocktails like White Russians, or to use in dessert recipes.
Place both types of sugar in a heat-proof mixing bowl.
Boil the water, then measure and pour it over the sugar. Stir or whisk it until the sugar is completely dissolved.
Add the instant coffee and whisk it in, too, until it is completely dissolved.
Add the vanilla, either from the pod or as liquid vanilla extract. With a vanilla pod, slice along the side, and scrape the gooey insides out with a knife. Whisk it into the liquid.
Pour the white rum into the mix and stir gently.
If you would like even more vanilla flavor, add one vanilla bean to each 25.3 oz (750 ml) bottle. Make a slit along the side so that the flavor can infuse out. This is completely optional, though.
Then, using a funnel, pour the mixture into your chosen glass bottles and seal them. If any vanilla remains at the bottom of the bowl, spoon it out and into the bottles.
Stand the bottles of homemade Kahlua upright in a cool dark place, out of direct sunlight, and wait about two to three weeks before drinking it. This gives the flavors, especially the vanilla, time to infuse. If you absolutely can't wait that long, it's fine to drink any time after you've made it.*
Kept stored in a cool, dark place, homemade Kahula has a shelf life of about one year. It can last longer, though.
Notes
*If you prefer, you can make homemade Kahlua with strong brewed coffee. To do this, omit the instant coffee granules from the recipe and replace the cups of water with cups of coffee. Make the coffee as strong as possible, using at least double the amount of coffee grounds that you'd usually use. For a more authentic Kahlua, use Arabica coffee.*Homemade Kahlua is relatively flexible with the type of liquor you use. Though this recipe calls for white rum (or vodka) as the main alcohol, you can also use dark rum. *You can serve homemade Kahlua on its own over ice, or mix it into cocktails. Kahlua is the key ingredient in making White Russians, and to make your own, mix one shot of vodka with half a shot of homemade Kahlua and pour it into a glass. Top the drink with a drizzle of heavy cream, and then plop a few ice cubes on top.