Preheat the oven to 180°C/fan 160°C/gas 4. Grease a 23cm round cake tin and line the base with baking parchment.
Put the chopped dates in a bowl and pour over 175ml boiling water. Stir in the bicarbonate of soda and leave to cool.
In a large bowl, beat the butter and sugar together until light and fluffy. Beat in the eggs one at a time, then fold in the flour, baking powder and vanilla. Fold in the cooled date mixture.
Spoon the mixture into the prepared tin and bake for 40-45 mins until a skewer inserted into the centre comes out clean. Leave to cool in the tin for 10 mins, then turn out onto a wire rack.
For the sauce, melt the butter, sugar and cream in a pan over a medium heat, stirring occasionally, until thickened slightly. Drizzle the sauce over the warm pudding to serve.
