One of my favorite summer treats! I remember searching the woods for enough blackberries for my mother to make Blackberry Mousse. She would spread it in a pyrex dish and scoop it out with an ice cream scoop. I like to use the muffin tins. After they are frozen you can take them out of the pan and put them in large ziplock freezer bags and take them out as individual servings. It is best if you let them thaw slightly before eating.