Whip up a big pitcher of these refreshing summertime gin cocktails at your next backyard BBQ.
Add blueberries, sugar, and ½ cup water to a boil in a medium saucepan and stir until the sugar dissolves. Reduce heat and simmer for about 20 minutes until the blueberries have released most of their juice. Strain the blueberry mixture through a fine-mesh strainer into a bowl or pitcher. Press on the berries to squeeze out as much liquid as possible and discard the solid part of the berries.
If it's not already in a pitcher, pour the syrup into a pitcher, and then add the gin and lemon juice. Add enough ice to fill the pitcher and stir until the mixture is well chilled.
Fill glasses with ice cubes and fill about 3/4 full with cocktail mixture. Top each glass with about ¼ cup of club soda. Garnish with lemon slices, if you'd like.