In small saucepan over medium heat, add dates and water. Bring to a low boil and cook until dates have softened and are starting to break apart, 5 to 10 minutes. Add butter and salt (if using). Pour into blender and purée until smooth. Store in heatproof jar, let cool, then store in fridge for up to a week.

Serve with sliced fruit, ice cream, yogurt, or even on your oatmeal in the morning.