Kahlua is dirt cheap in Mexico. Up here, it's really expensive. Here's my recipe:
9 or 10 Keurig coffee cups that you don't care for. I used Newman's along with a couple of French Roast. I have also made this with hotel coffee packs.
1 cup brown sugar
1/4 cup agave nectar
A split vanilla bean or two, or a teeny bit of vanilla extract
Boil about 2 quarts of water with the coffee grounds for 30 minutes or so. Strain through a sieve lined with coffee filters, after you think it looks dark enough, and add the sugars. Cook some more. When it thickens up, take off the heat, pour into a Mayan Goddess bottle, and add enough vodka, rum, or everclear to make up the difference. If you're using the vanilla bean, poke them in the bottle too. It will creep out your husband if you don't tell him what they are. The reaction is worth it.
She who dies with the most toys, wins.