Preheat the oven to 350 degrees F. Grease and line a 9" square pan with parchment paper.

Soak cake strips in ice cold water.

In a medium bowl, whisk together the flour, sugar, cocoa powders, espresso powder, baking powder, and salt. Set aside.

In a large bowl, whisk together the milk, oil, eggs, and vanilla.

Add the dry ingredients to the wet, and whisk until just combined.

Lastly, whisk in the hot coffee until fully combined.

Pour the batter into the prepared square pan. Wrap the cake strips around the pan and bake for about 25 minutes or until a toothpick inserted comes out clean.

Allow cake to cool completely in the pan.

Remove the cake and use a serrated knife to cut the cake in half lengthwise, then each of those halves widthwise to create four rectangles measuring 4"x8" roughly. You may need to trim each rectangle even more to fit into your loaf pan.

In a large heat proof bowl, vigorously whisk together the egg yolks and half (75g) of the sugar until light in color and flows off of the whisk.

Place the bowl over a small pot of simmering water. Frequently whisk the mixture for about 5 minutes or until the sugar has completely dissolved.

Remove the bowl from the double boiler and place in the fridge to cool for about 10 minutes.

Once cool, whisk in the cold mascarpone until fully combined. Set aside.

In a medium heat proof bowl, whisk together the egg whites and remaining (75g) of sugar.

Place the bowl over the pot of simmering water, and whisk frequently until it reaches 120 degrees F.

Remove from heat and use an electric mixer to beat until stiff peaks form.

Using a rubber spatula, gently fold the meringue into the egg yolk mascarpone mixture until just combined.

Assemble the cake immediately.

Line a pullman pan or 9x5 loaf pan with parchment paper, leaving the edges hanging over the sides for easy removal.

In a mug or measuring cup, combine the cooled coffee and rum.

Place the first cake layer into the pan and generously brush with the rum & coffee.

Use a 3 tablespoon cookie scoop to add 5 scoops of the tiramisu filling, then spread into an even layer. Repeat this until all cake layers have been added.

Brush the last cake layer with rum & coffee and top with the rest of the tiramisu filling.

Loosely cover the pan and place in the fridge overnight.

Just before serving the next day, remove the cake from the pan and generously sprinkle cocoa powder on top. Enjoy!