In this recipe I used 1/3 cup pomegranate balsamic vinegar topped up with regular balsamic vinegar to equal the 1/2 cup required. If you do not have pomegranate balsamic vinegar, regular balsamic vinegar will work nicely. To get fresh pomegranate juice, cut 1/4" or so off the top and bottom, quarter the pomegranate and cut each quarter in half. Place chunks in a bowl of cold water. Push out the seeds and they will sink to the bottom, leaving any pith floating on the water, making it easy to scoop away. Pulse the seeds in a blender or food processor and strain through a fine mesh sieve.