Preheat the oven to 350°F (180°C). Lightly grease an 8-inch (20cm) square baking pan and line it with parchment paper, leaving enough overhang to help lift out the pudding.

Place the chopped dates in a heatproof bowl. Pour the boiling water over them, add ½ teaspoon of the baking soda, and stir. Set aside for 12–15 minutes, until the dates are very soft.

Use an immersion blender to blend the dates and soaking water into a mostly smooth purée. A few tiny flecks of date are fine. Set aside to cool until warm rather than piping hot.

In a large mixing bowl, beat the vegan butter and dark brown sugar with an electric mixer for 2–3 minutes, until lighter, creamy, and slightly fluffy. Scrape down the bowl as needed.

Add the vegan yogurt and vanilla. Beat until combined. The mixture may look slightly separated at this stage; that is okay.

In a separate bowl, whisk together the flour, baking powder, cinnamon, sea salt, nutmeg, if using, and the remaining ½ teaspoon baking soda.

Add one-third of the dry ingredients to the butter mixture and mix on low just until mostly incorporated. Mix in half of the warm date purée. Continue alternating the dry ingredients and date purée, ending with the dry ingredients.

Use a flexible spatula to gently fold the batter a few times, making sure no pockets of flour remain. Avoid vigorously mixing or beating the finished batter. It should be thick, soft, and easily spreadable—not pourable like pancake batter.

Transfer the batter to the prepared pan and smooth the top. Bake for 35–42 minutes, or until the top is risen and set, the center springs back when lightly pressed, and a toothpick inserted into the middle comes out with a few moist crumbs but no wet batter.

Place the pan on a wire rack and let the pudding rest for 10 minutes.

While the pudding bakes, combine the vegan butter, brown sugar, coconut milk, molasses, and sea salt in a medium saucepan over medium heat.

Cook, stirring frequently, until the butter has melted and the mixture is completely smooth.

Bring to a gentle simmer, then reduce the heat to medium-low. Simmer for 8–12 minutes, stirring frequently, until glossy and thick enough to lightly coat the back of a spoon. Coconut milk can take a few minutes longer to reduce than vegan heavy cream.

Remove from the heat and stir in the vanilla. The sauce will thicken substantially as it cools, so take it off the heat while it still pours easily.

While the pudding is still warm, use a skewer or toothpick to poke holes across the surface, stopping about halfway through the sponge rather than piercing all the way to the bottom.

Slowly spoon approximately ¾ cup (180ml) of the warm toffee sauce over the pudding. Give the sauce a few minutes to settle into the surface before adding more. Let the pudding rest for 10–15 minutes.

Cut into nine thick squares. Serve warm with additional toffee sauce and vegan vanilla ice cream or whipped cream. Finish with a small pinch of flaky sea salt, if desired.