Use a two-quart pitcher to mix the purée with the club soda in batches if making all 12 servings for this recipe. This recipe is from Anna Wallace, owner of Seattle Seltzer Company.
- 1 tablespoon black peppercorns
- 2 pounds very ripe blackberries, plus more for serving
- 2 fresh bay leaves, plus more for serving
- 9 cups club soda, divided
- Lemon wedges (for serving)
Crush peppercorns with a mortar and pestle or the side of a chef’s knife.
Pulse 2 lb. blackberries in a food processor until all berries are broken up but a few larger pieces remain. Strain through a fine-mesh sieve into a medium bowl, pressing down on solids to extract as much liquid as possible; discard solids. You should have about 3 cups very thick purée. Add crushed peppercorns, sugar, salt, and bay leaves and stir until most of sugar is dissolved. Transfer to a 1-qt. jar or an airtight container. Cover and chill 8–12 hours.
Strain purée through clean sieve into another medium bowl (you’ll have about 3 cups); discard solids.
To make 1 drink, mix ¼ cup purée with ¾ cup club soda in a measuring glass; taste and add more purée if you want it sweeter. Pour into an ice-filled glass. Garnish with a lemon wedge, a bay leaf, and a few blackberries.
Do Ahead: Purée can be infused and strained 3 days ahead. Cover and chill.