Place berries and sugar in a medium non-stick saucepan, and bring to a simmer, stirring frequently. Cook for 5 minutes. Pour cooked berries and syrup into a colander resting over a large bowl. Allow the berry syrup to drain. Return the syrup to the pan, and bring to a boil over medium-high heat. Reduce heat to medium, and reduce the syrup until thickened, about 20 minutes.