A touch of honey mellows the fresh ginger and lemon in this refreshing fizzy drink. If you make the base in advance, the soda comes together in mere seconds.
Blend ginger with 1/2 cup water until smooth. Strain, pressing on solids to yield 1/2 cup juice. Stir together ginger juice, lemon juice, and honey. Ginger base can be stored in an airtight container in the refrigerator up to 1 week. (It makes enough for 10 drinks.)
Fill a glass with ice and add 2 tablespoons ginger base. Top with seltzer and garnish with a slice of ginger.
Ginger juice (without the honey and lemon) can be frozen up to 3 months. Defrost before using.