- 1 (4-inch) piece peeled ginger, coarsely chopped
- 1 4-inch piece peeled turmeric, coarsely chopped, or 1/2 teaspoon dried turmeric
- 1/3 cup honey
- 1/4 cup fresh lime juice
- 2 teaspoons black peppercorns
- 1 tablespoon chia seeds
- Club soda (for serving)
- Thyme sprigs (for serving; optional)
- Blend ginger, turmeric, honey, lime juice, black peppercorns, and 3 cups water in a blender until smooth. Strain through a fine-mesh sieve into a large bowl. Stir in chia seeds and let sit until seeds begin to swell, 8–10 minutes.
- Divide tonic among ice-filled glasses. Top off with club soda and garnish with thyme sprigs, if desired.
- Tonic can be made 1 day ahead. Cover and chill. Stir vigorously before topping off with club soda.