- Preheat oven to 350°. Butter a baking dish . A 9 inch round pan or 9*5 rectangular baking pan will be good.
- In a medium bowl, pour water over dates; stir in baking soda, and let stand until dates soften, about 5 minutes. In another medium bowl, combine flour, baking powder, and salt; set aside.
- In the bowl of an electric mixer, cream butter and sugar together until fluffy. Beat in eggs, one at a time, until almost smooth. With mixer on low, beat in flour mixture until just combined; add date mixture and vanilla until blended. [if the dates are not melted enough mash is lightly using a spoon ]
- Transfer batter to prepared pan. Bake until top feels firm, 30 to 33 minutes.
- Meanwhile, to make toffee sauce: In a medium saucepan, bring heavy cream and light brown sugar to a boil, stirring occasionally. Add butter, and boil 3 minutes.
- Remove pudding from oven; let stand 5 minutes. Using a fork, poke holes in surface of pudding so toffee sauce will seep in evenly. Spoon 6 Tablespoons sauce, one at a time, over top. Serve remaining sauce alongside warm pudding, with a bowl of whipped cream, if desired.