In a medium saucepan over medium heat, melt the butter.

Add the brown sugar, salt, and heavy cream. Stir with a rubber spatula until blended.

Bring the mixture to a boil, then reduce heat and simmer for 4–5 minutes, scraping down the sides.

Remove from heat, then stir in vanilla extract, pumpkin puree, and cinnamon.

Transfer sauce to a container to cool. Set aside

Preheat oven to 350°F (175°C). Grease a 9x9-inch baking pan with cooking spray or shortening and line with parchment paper.

In a medium bowl, combine chopped dates, melted butter, baking soda, and baking powder. Pour boiling water on top, stir, and let sit for 20 minutes until dates have softened.

In another medium bowl, whisk together flour, cinnamon, pumpkin pie spice, and salt. Set aside.

Once softened, mash the date mixture slightly with a fork.

In a large mixing bowl, combine pumpkin puree, sour cream, brown sugar, molasses, oil, eggs, and vanilla. Stir in the date mixture until smooth.

Add the dry ingredients into the wet ingredients, mixing gently with a spatula until just combined. Do not overmix.

Pour the batter into the prepared pan, spreading evenly.

Bake for 55 minutes, or until a toothpick inserted in the center comes out clean or with moist crumbs.

Cool in the pan for 10–15 minutes.

Use a chopstick, skewer, or the end of a wooden spoon to poke holes all over the cake.

Pour ⅔ of the pumpkin butterscotch sauce over the warm cake to let it soak in.

Slice into squares and serve warm.

Top with a drizzle of extra butterscotch, a sprinkle of flaky sea salt, and a scoop of vanilla ice cream or whipped cream.