Preheat oven to 350º Fahrenheit and spray a 9" square inch pan with cooking spray.
Whisk together cake mix with spices in a large mixing bowl.
In another bowl, use a whisk to mix the oil, water, molasses, and eggs until combined.
Add the dry ingredients to the wet mixture and mix until combined.
Pour the batter into pan and bake at for 35-40 minutes, or until golden brown and a toothpick inserted into the centre of the cake comes out with only a few crumbs.
Remove the cake from the oven, put the pan on a wire rack and cool for 10 minutes.
Poke holes in the warm cake halfway through with a large meat fork, about an inch apart.
Drizzle warm eggnog over the cake, making sure it goes into the holes. Make sure the eggnog is warmed and thin enough, so that it easily enters the holes.
Cover with plastic wrap and chill in the fridge for at least 4 hours or overnight.
Whip the whipping cream and confectioners sugar in a bowl with an electric hand mixer until stiff peaks form.
Spread whipped cream on top of the cooled cake.
Make the ginger crumble:
Mix together the oats, flour, brown sugar and butter. Spread on a 9x13 baking sheet. Bake in an oven (preheated to 350º Fahrenheit) for 10 minutes.
Sprinkle the cooled ginger crumble over the cake and drizzle with caramel topping.
Store in an airtight container in the refrigerator.
The calories shown are based on the cake being cut into 12 pieces, with 1 serving being 1 slice of cake. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information.**