down the side to keep as much fizz as possible. You’ll see the dark liquid bubble up around the ice.
Give each jar a gentle stir with a long spoon—just a few turns—to mix the coconut-lime with the diet cola while still keeping some lighter and darker streaks.
Right before serving, slowly pour about 2 tablespoons of very cold heavy cream into the center of each jar. Let it sink and swirl on its own for a moment; you’ll see creamy ribbons
