Butter a 9½-inch (24 cm) square brownie pan and line the bottom and sides with parchment paper. Preheat the oven to 340°F (170°C), using the convection setting.

Place the chopped chocolate and softened butter in a bowl and melt them together over a double boiler or in the microwave, stirring until smooth and fully combined.

Add both types of sugar and whisk until the sugar begins to dissolve and the chocolate mixture cools slightly.

Add the vanilla, salt and one egg, whisking thoroughly to incorporate. Gradually add the remaining eggs one at a time, whisking well after each addition.

Finally, sift the flour over the mixture and gently fold it in with a spatula until just combined.

Pour the batter into the prepared pan and smooth the surface.

Bake in the preheated oven for about 25 minutes, until the center is set.

As soon as the brownie comes out of the oven, poke holes all over the surface with a skewer. Drizzle with the espresso and coffee liqueur, if using.

Allow the brownie to cool completely, then sprinkle the grated chocolate over the top.

Meanwhile, prepare the mocha cream.

Using a hand mixer, beat the softened cream cheese and heavy cream in a bowl for a few seconds, just until combined.

Add the instant coffee and sugar and continue beating for 1–2 minutes, until light and fluffy. Be careful not to overbeat the mixture, as it may curdle and become lumpy.

Spread the mocha cream evenly over the cooled brownie with a spatula. Refrigerate for several hours, ideally overnight.

When ready to serve, dust the entire surface with cocoa powder and cut into pieces.