In a stand mixer, beat 8 eggs until foamy. Then slowly add the sugar and vanilla while the mixer is still beating.
Sift the flour, baking powder, and cornstarch. Then fold it into the beaten eggs using a whisk.
Line 2 round baking pans (10 inches in diameter) with parchment paper and spray with nonstick spray. Then distribute the batter evenly between the two pans.
Bake in a preheat the oven to 350 degrees Fahrenheit and bake for 28-30 minutes. Then transfer to a cooling rack.
Make the tiramisu cream
Meanwhile combine the cream cheese, mascarpone cheese, powdered sugar, and Kahlua in the bowl of your stand mixer. If your mascarpone cheese has a runny consistency, refrigerate this mixture for 40 minutes before adding in the egg product.
In a separate bowl beat the egg product with an electric mixer until it becomes thick and creamy. This should take about 5-7 minutes. Add the egg product to the cream cheese mixture and mix just to incorporate. If you don't have egg product, see notes below on how to make this cake without it.
Make the coffee soak
In a small bowl mix together the espresso, with 3 tbsp Kahlua and 1 tbsp sugar.
Slice, soak, and assemble the cake
Slice each cake in half so you are left with 4 thin slices. Soak each layer of cake with the espresso and Kahlua mixture. I find that using a Martellato soaker bottle works best.
Then begin layering the cake in this order: 1 layer of soaked cake, 1 1/4 cup cream cheese mixture, and cocoa powder. Repeat this until you stack the last layer of cream. At this point, you can decorate the sides and top of the cake with extra cocoa or cream.
Coffee substitute options For 1 cup of espresso coffee, use 1 cup of hot water with 1 tsp of instant espresso powder. Or you can brew 1 cup of very strong coffee. How to freeze the cakeTo freeze tiramisu, leave off the cocoa topping and wrap the cake with plastic wrap (twice) once its frozen solid, wrap tightly in foil. You can keep it frozen for up to 3 months. Thaw in the fridge overnight before serving.Cant find egg product? make your own!If you prefer to use real eggs over egg product, add 1/4 cup granulated sugar to 3 eggs instead of the egg product.Bring a pot of water (about 2 cups) to a simmer. Place the sugar and eggs into a bowl and place the bowl over the simmering pot. Using an electric mixer beat the eggs and sugar until they double in size and remove from heat. Once the eggs are cooled add them to the remaining cream ingredients.