Line a 9×5-inch loaf pan with foil (leave some foil overhang to lift the tiramisu out later) and spray the foil with cooking spray; set the pan aside.

Slice the 13.5–16 ounce pound cake in half lengthwise into two large slabs. Place the bottom slab in the prepared pan and set the top slab aside.

In a large glass measuring cup, combine 3/4 cup brewed espresso and 1/2 cup coffee liqueur; stir to combine. Drizzle about half of this coffee mixture evenly over the cake layer in the pan and set the remaining coffee mixture aside.

In a large bowl, add 8 ounces softened mascarpone cheese, 1.25 cups confectioners’ sugar, and 1 pint (16 ounces) heavy whipping cream. Using a handheld electric mixer on high speed, beat the mixture about 4 to 5 minutes, or until it is quite stiff and holds peaks.

Evenly spread about half of the cream mixture (about 1 1/2 cups) over the soaked cake layer in the pan.

Take the reserved top cake slab and poke about 30 holes in its top surface with a fork to help the coffee mixture soak in.

Place the top cake slab over the cream layer in the pan. Slowly and evenly drizzle the remaining coffee mixture over the top layer; allow it to absorb (some liquid may pool or run down the sides).

Evenly spread the remaining cream mixture (about 1 1/2 cups) over the top of the assembled cake.

Cover the pan and chill the tiramisu in the refrigerator for about 3 hours to set.

Just prior to slicing and serving, sift about 1/4 cup unsweetened natural cocoa powder evenly over the top, remove from the pan using the foil overhang, slice, and serve.