Preheat the oven to 350° and butter six ½-cup ramekins. Set on a rimmed baking sheet.

In a small saucepan, combine the dates, instant espresso powder with ¾ cup of water. Bring to a simmer over moderately-low heat and cook, stirring occasionally, until the water is nearly absorbed and the dates are soft, about 15 minutes. Transfer the dates and any liquid to a food processor and puree until very smooth.

Meanwhile, in a small microwave safe bowl, microwave the chocolate on HIGH in 20 second intervals until beginning to melt. Stir until smooth and completely melted.

In a small bowl, combine the flour, baking powder, baking soda and salt. In the bowl of a stand mixer fitted with a paddle or in a medium bowl and using a hand mixer, beat the brown sugar with the 4 tablespoons of butter at medium speed until light and fluffy. Beat in the egg and vanilla, then beat in the date puree and melted chocolate. At low speed, beat in the dry ingredients until just combined. Spoon the batter into the ramekins and smooth the tops. Bake for 20 to 25 minutes, or until a toothpick inserted into the centers comes out with a few crumbs.

In a medium saucepan, combine the brown sugar and butter. Cook over moderate heat, whisking occasionally, until the butter has melted and the sugar has dissolved, 3 to 5 minutes. The mixture will bubble—lower the heat, if necessary. Add the chocolate and salt and whisk until the chocolate is melted and the sauce is smooth. Add the cream—the sauce will bubble up. Continue cooking, whisking frequently, until the toffee sauce has thickened slightly, about 5 minutes. Remove from the heat and stir in the vanilla.

When the puddings are finished baking, transfer the baking sheet to a cooling rack. Using a skewer, poke holes in the top of each pudding. Spoon 2 to 3 Tablespoons of sauce over each pudding, letting it absorb between each tablespoon. Let sit for 10 minutes.

Run a knife around the edge of each pudding and turn out onto six dessert plates. Alternatively, you can serve the puddings in the ramekins. Spoon more chocolate-toffee sauce over each pudding and serve with a scoop of vanilla ice cream or a dollop of whipped cream.