"You can infuse flavors into liquor (and water based things, too) almost instantly with nothing more than an [nitrous] Cream Whipper. You can use seeds, herbs, spiced, fruits, cocoa nibs, etc. Here’s how:

Put room-temperature booze into the cream whipper. Add herbs, seeds, whatever. Close the whipper and charge it with nitrous oxide (N2O –the regular whipped cream chargers). Swirl gently 30 seconds and let stand 30 seconds more. Quickly vent the N2O out of the whipper, open it, and strain out the infusion. Done."