Place a small saucepan over medium-high heat. Place all the ingredients for the cranberry sauce in the pan and bring to a boil. Lower the heat a little and simmer for 10-15 minutes to thicken. The sauce should be a thin jelly consistency that will thicken when it chills. Remove from heat and place in the fridge.
For the gingerbread, grease an 8x8-inch baking dish and preheat the oven to 325 degrees F. In a large bowl, whisk the oil, sugar, molasses, egg, spices and salt together until smooth. Slowly add the flour and whisk until well combined.
Heat 1/2 cup tap water until it’s hot to the touch. Mix the baking soda into the hot water, then slowly whisk the water into the batter. Pour the batter into the baking dish and bake for 45 minutes.
Once cooled flip out of the pan and cut into 1-inch cubes.
For the pumpkin cream, whip 1 cup of heavy cream with an electric mixer. Set the whipped cream aside, and using a separate bowl, beat the cream cheese, pumpkin puree, sugar and pumpkin pie spice together until fluffy and smooth. Scrape the bowl and gently beat the whipped cream into the pumpkin mixture.
Once the cranberry sauce has chilled, start layering the gingerbread trifle: 1/3 cake cubes on the bottom, 1/3 pumpkin cream, half the cranberry sauce. Repeat. On the top, place the last 1/3 of gingerbread cubes and top with the last of the pumpkin cream. Garnish with fresh pomegranate arils. You should have 3 layers of cake, 3 layers of cream, and 2 layers of cranberry.
QUICKIE VERSION: The holidays can be crazy! Make this even faster by buying gingerbread cake at a bakery and GOOD pre-made cranberry sauce from a gourmet grocery store. Make the pumpkin cream and layer as directed.