Blueberry Chocolate Ice Cream

Peel the banana and cut into chucks. Put banana, blueberries and cacao powder in a blender and mix. Place the banana mixture in a freeze-proof container and freeze 2 to 3 hours. After each hour, use a spoon or fork to stir the content and put back in the freezer. When ready to eat, use a spoon to mash it and place in a serving plate. Garnish with a blueberry (optional)