Preheat the oven to 350 degrees F. Lightly grease a 12-cup muffin tin or ramekins.
Add the dates to the bowl of a food process or blender and pour boiling water on top. Set aside for 5 minutes.
Meanwhile, prepare the batter: Cream together butter and brown sugar. Add eggs, one at a time, beating after each addition. Add the molasses and vanilla and mix.
Notes
Store the cakes and sauce (in an airtight container) separately for up to five days in the refrigerator.