Grease deep 20cm round cake pan; line base with baking paper.
Combine dates and the water in food processor. Stir in soda and keep aside. .
Cream butter and sugar till creamy.
Add eggs and vanilla essence.
Mix in dates.
Fold in flour and pour mixture into pan.
Bake, uncovered, about 1 hour.
Make butterscotch sauce by stirring ingredients in small saucepan over low heat until sauce is smooth and thickened slightly.
Once cake is out of the oven, poke some holes in the cake using a skewer.
Drizzle ½ cup of the warm sauce over the cake. Reserve the rest of the sauce to top the cake with when ready to serve.Pour half of the sauce over the cake.