1. In a mortar and pestle, or a resealable bag and rolling pin, crush anise pods and fennel and coriander seeds. Toast together in a skillet over medium-high until fragrant, about 1 minute. Divide between 2 quart-size glass jars, then divide vodka evenly between jars. Let cool completely. Screw lids onto jars, shake gently, and let stand in a cool, dark place 5 days.

2. Strain vodka mixture through a fine-mesh sieve lined with cheesecloth; discard solids. In a small pot, boil sugar and 1 1/4 cups water just until sugar dissolves; add to strained vodka. Let cool completely, then refrigerate until cold, 1 hour. Divide among eight 8-ounce gift bottles. Bottles will keep in refrigerator up to 6 months. To serve, pour 1.5 ounces directly over ice, or add 1 part anisette and 3 parts cold water to a glass filled with ice.