Place diced avocados in bowl.
Score the pomegranate and place in a bowl of water. Break open the pomegranate to free the arils. The arils will sink to the bottom of the bowl and the membrane will float to the top. Sieve and put the arils into a separate bowl.
Add one-fourth cup pomegranate arils and the remaining ingredients to the diced avocados. Mix well. Add salt and pepper to taste.
Place guacamole in a serving bowl and sprinkle remaining pomegranate arils on top for garnish. Add additional garnish of sour cream and cilantro, if desired. Serve with assorted color tortilla chips.