Make the cake: Preheat oven to 350 degrees. Butter a Bundt cake pan.
In a small saucepan, add dates and water. Heat until dates are soft, about 15 minutes. Using a food processor or blender, blend date and water mixture until smooth; set aside.
Using an electric mixer, cream together the butter and sugar until light and fluffy. Add eggs, vanilla extract, orange zest and date mixture. Mix until combined. Add dry ingredients and mix again.
Pour batter into Bundt pan and bake for 30 to 40 minutes. Cool cake in pan on wire rack for 20 minutes before removing.
Make the sauce: In a small saucepan, combine all sauce ingredients except vanilla. Bring to a low boil and cook for 5 to 10 minutes, stirring constantly until mixture is thickened and sugar has melted. Remove from heat and stir in vanilla.
To assemble: Transfer cooled cake to a serving platter and the pour sauce into the center reservoir. Slice and watch the volcano erupt with sticky toffee goodness!