To make Marie Simmons’ English sticky toffee pudding, first preheat the oven to 350 degrees Fahrenheit. Sift together 1 cup and 1 tablespoon of flour and 1 teaspoon of baking powder. Finely chop 3/4 cup of pitted dates, and bring 1 1/4 cups of water with 1 teaspoon of baking soda to a boil. Add the dates to a small bowl, and pour the boiling water over them.
In a separate bowl, thoroughly combine 1/4 cup of unsalted softened butter and 3/4 cup of granulated sugar with an electric mixer. Mix in 1 large egg and 1 teaspoon of vanilla, and continue to beat the mixture until the eggs and vanilla are completely incorporated. Slowly add the dry ingredients while continuing to beat the mixture.
Turn off the beater, and fold in the chopped dates and liquid with a rubber spatula. Transfer the batter to a greased 10-inch baking dish. Bake the dish until it sets and the top is firm, approximately 35 minutes.
To make the sticky toffee sauce, bring 1/2 cup of unsalted butter, 1/2 cup of heavy cream and 1 cup of packed light brown sugar to a boil in a saucepan. Reduce the heat to medium-low, and continue to simmer the sauce until it is thick, approximately eight minutes.
Set the oven to the broiler setting. Spread 1/3 cup of the toffee sauce over the top of the baked pudding, and broil the dish until the topping bubbles, approximately one minute. Serve the pudding with the remaining toffee sauce and whipped cream.