1. Preheat the oven to 350°F. Line an 8-inch cake pan with parchment paper or a silicone baking mat and grease & dust the edges with a combination of flour and cocoa powder.
2. In a large mixing bowl, combine the sugar, vegetable oil, eggs and vanilla extract. Beat on medium speed until the eggs and oil are well incorporated and the batter is lighter in color. Next mix in the sour cream and beat until well combined.
3. In a separate bowl, sift together the dry ingredients. Then alternate adding half the dry ingredients followed by half of the coffee and mix just until the flour starts to incorporate. Use a spatula to scrape down the sides of the bowl and stir the batter from the bottom to the top to ensure it’s well mixed.
4. Bake at 350°F for 28-30 minutes. Test the cake for doneness by inserting a toothpick into the center of the cake. If the toothpick comes out clean, the cake is done. Cool Completely.

To assemble:

1. About 20-30 minutes before you’re ready to assemble remove the ice cream from the freezer and allow it to soften. Then level off the top of your cake so it’s flat. Set aside top piece of cake that you cut off because it’s being mixing it back into the ice cream. Place the cake layer in the freezer.
2. Transfer the cake layer to an 8-inch springform pan, or line your cake pan with plastic wrap or parchment paper along the bottom and up the sides if you want to remove the cake from the pan. If it fits, place a cake board in the bottom of the pan. Place the cake layer in the bottom of the pan.
3. Measure out about 3 cups of ice cream, crumble the extra chocolate cake and then mix together.
4. Evenly spread the ice cream over the layer of cake. Refreeze the cake for 2-4 hours until the ice cream has refrozen.

For the whipped cream topping

1. Prepare the whipping cream. Chill the bowl in the freezer or refrigerator for 5-10 minutes.
2. Pour the heavy whipping cream into the chilled bowl and use an electric mixer to beat the heavy cream on medium-high speed until the cream starts to thicken to soft peaks. Slowly add the powdered sugar, cocoa powder and vanilla extract, beating until combine. Then continue beating on high speed until stiff peaks form.
3. To frost the cake, remove it from the pan and place the whipped cream in a large piping bag and pipe it around the outside edge of the cake and on the top. Gently smooth with an angled spatula. Decorate with leftover whipped cream. Refreeze for 30-60 minutes before slicing.