1. Rinse blueberries, removing any remaining stems or unripe berries. Do not dry.
2. Add wet blueberries to medium-sized pot and add sugar and 1/4 cup of water.
3. Turn stove to low and stir blueberries occassionally.
3. When blueberry mixture is getting warm, add butter and increase temperature to medium. Stir for 5 minutes.
4. Take blueberries off heat. Add half of blueberries to blender. Blend until smoothe. Return blended blueberries to pot.
5. Stirring constantly, bring mixture to a boil. As soon as a boil is reached, remove from heat.
6. Serve immediately over ice cream, pan cakes, etc., or chill for later use.