4 cups blackberries, picked over
6 juniper berries, or a shot of London dry-style gin if juniper berries are not available
8 black peppercorns
1 small bay leaf
1/2-inch piece fresh ginger, sliced
3 allspice berries
2 cups red wine vinegar
6 tablespoons sugar
3 tablespoons kosher salt
1 sprig fresh thyme
1 shallot, quartered
1. Fill a clean 1-quart jar with blackberries and place in the refrigerator. With a mortar and pestle, lightly crush the juniper berries, peppercorns, bay leaf, ginger, and allspice.
2. In a medium saucepan over high heat, combine the vinegar, sugar, salt, and 2 cups water, and stir to dissolve the sugar. Add the crushed spices, thyme, and shallot. When the mixture comes to a boil, reduce the heat and simmer for 10 minutes. Remove from the heat and cool to room temperature. Strain out the solids and discard. Chill the liquid for 1 hour. Pour the cooled brine over the berries. Cover and refrigerate for up to 4 weeks.