Preheat oven to 375°F (180 °C). Butter an 8-inch (20 cm) square baking pan. Cover the bottom of another larger baking pan with hot water about ¼ full.
For the pudding, chop the dates coarsely, place them in a small saucepan with the water and bring to a boil for 5 minutes. Remove the saucepan from the heat, mix in the baking soda and let stand for 20 minutes.
In a large mixing bowl, add muffin mix, ground ginger, 2 eggs and melted butter and blend well at low speed. Finally, add the date mixture and combine all the ingredients well.
Pour the mix into the prepared baking pan and sit the pan in the water bath. Bake for 25 minutes, then reduce to oven temperature to 350°F (150 °C) until the cake is cooked, 30 more minutes, or until a toothpick comes out clean when inserted in the middle. Cut in 8 squares.
For the toffee sauce, melt the butter and dissolve the sugar in it over medium heat. Add the cream and vanilla; simmer for 5 minutes until thickened slightly, stirring to incorporate.
Serve the pudding warm with warm toffee sauce. The pudding can be made ahead and kept refrigerated until needed. It can be reheated by steamer, or lightly microwaved before serving. Serves 6 –8 .