Make the Spice Cake. Preheat the oven to 350 degrees F. Grease an 8x8” or 9x9” cake pan well or line with parchment paper. Set aside.
Combine the flour, baking soda, salt, ginger, cinnamon, cloves, allspice, and nutmeg in a medium bowl. Set aside.
In a 1 to 2-cup measuring cup or medium bowl, combine the vanilla, molasses, and buttermilk. Set aside.
In a stand mixer fitted with the paddle attachment, or using a hand-held mixer, beat the butter on medium speed until fluffy. Add the sugars and continue to mix on medium speed for another minute, or until fully combined and fluffy.
Add the egg and combine thoroughly. Scrape down the sides of the bowl and paddle.
Turn the mixer to low and add about a third of the dry ingredients. Mix until just combined.
Add about half of the liquid ingredients and mix until just combined. Continue alternating with the ingredients until all have been added, scraping the bowl and paddle as needed.
Scrape the batter into the prepared cake pan. Smooth the top evenly, spreading to the corners.
Bake in the preheated oven for 30 to 35 minutes, or until a toothpick inserted into the center of the cake comes out clean or with a few crumbs, but no wet batter.
Remove the cake from the oven and let it cool in the pan for 20 minutes. Invert onto a cutting board or cake plate and cool completely before using.
While the cake is cooling, keep the oven at 350 degrees F. Line a rimmed baking sheet with parchment paper. Set aside.
Make the Pumpkin Buttered Pecans. In a medium bowl, combine the melted butter and vanilla. Add the pecans and toss to coat thoroughly. Sprinkle in half of the sugar and a small pinch of salt, toss, add the remaining half of the sugar and toss once more.
Spread the pecans in one layer onto the parchment-lined baking pan.
Bake in the preheated oven for 5 minutes. Stir well, and bake for another 5 minutes.
Remove the pecans from the oven. Carefully remove the parchment paper onto a cooling rack for the nuts to cool completely before using or storing in an airtight container. (The pecans can be made up to 2 days in advance.)
Make the Pumpkin Whipped Cream. In a stand mixer fitted with the paddle attachment, (alternatively, you can use a hand-held mixer), add the cream cheese to the mixer bowl. Whip until smooth and fluffy. Add the pumpkin and combine well. Set aside.
In another mixer bowl, whip the heavy cream, confectioners’ sugar, and vanilla until stiff peaks form.
Fold the sweetened whipped cream into the pumpkin mixture.
Prep and Layer. Cut the cake into bite-sized pieces.
Using a whisk or a spoon, stir the fig spread to loosen it.
In a trifle bowl or individual glasses, begin to layer all the components. Place a layer of cake pieces, spread with a layer of the Pumpkin Whipped Cream, and dollop some of the fig spread. Repeat these layers ending with Pumpkin Whipped Cream. Top with the pecans.
Cover with plastic wrap and chill for about an hour (if you can wait), and serve. Leftovers can be kept well-covered in the refrigerator for up to 3 days.