3/4 pound (12 ounces, 340 grams or about 2 1/4 cups) dried Medjool dates, pitted and chopped (my favorite online source is Nuts.com; Costco also sells an organic brand that I like, though the name escapes me)
2 cups boiling water
1 ½ teaspoons baking soda
½ cup (1 stick, 4 ounces or 113 grams) unsalted butter, melted
1 cup plus 2 tablespoons (215 grams) dark brown sugar
2 teaspoons vanilla extract
⅛ teaspoon salt (or more, if desired)
Coarse sea salt
More mascarpone, lightly sweetened whipped cream, or ice cream
Combine the dates and the boiling water in a heatproof bowl and let sit for 30 minutes. Meanwhile, heat the oven to 350°F (175°C) and line a 9-inch round cake pan with parchment paper (or butter it, if you prefer).
Blend the date-water mixture in a blender or food processor until smooth. Stir in the baking soda and set aside. In a large bowl, whisk together the melted butter, brown sugar, and molasses. Whisk in the eggs one at a time. Using a rubber spatula or wooden spoon, gently fold in the flour, then the date puree. Pour the batter into the prepared pan and bake for 50-60 minutes, until a toothpick inserted into the center comes out with just a few crumbs attached. Let the cake cool in the pan for 20 minutes.
Meanwhile, make the toffee sauce. Combine the butter, mascarpone, brown sugar and vanilla extract in a 2- or 3-quart saucepan over medium heat. Bring the mixture to a simmer and let cook for about 10-15 minutes, whisking, until the sauce thickens and coats the back of a spoon. Stir in the salt, and set aside.
Turn the cake out onto a cooling rack and remove the parchment paper, if using. While the cake is still warm, slice into desired portions and drape each slice with a generous amount of toffee sauce and a pinch of coarse sea salt, plus more mascarpone or whipped cream if desired. Enjoy!
For a cake that veers even more into that warm, rich holiday gingerbread territory, use the higher range of the spices listed below. You could even stir in a teaspoon or two of freshly grated ginger.