In a large container, whisk together the vodka or gin (if using), lemon juice, and blueberry jam. Store the lemonade concentrate in the refrigerator for up to 2 days until ready to serve.
If using water, in a large pitcher combine the lemonade concentrate and 5 cups of filtered water and stir to combine. To serve, fill glasses three quarters full with crushed ice and pour over the lemonade. Top with a few pieces of torn basil leaves and a sliced lemon.
If using club soda, do not premix it with the concentrate, as the carbonation will go flat. Instead, prepare each glass fresh. To serve, fill glasses three quarters full with crushed ice. Pour in about 3 1/3 ounces of the lemonade concentrate, then add about ½ cup of club soda. Top with a few pieces of torn basil leaves and a sliced lemon.