Preheat the oven to 350F degrees. Line an 8x8 inch pan with parchment paper so there's an overhang around the edges. Or line with aluminum foil and lightly grease.

In a large microwave-safe bowl, add the chopped chocolate, butter and instant coffee. Microwave for 45-second intervals on medium power, stirring between each interval until melted. Alternatively, melt in a double boiler over low heat.

Allow the mixture to cool slightly, then whisk in the sugar, whisked eggs and vanilla extract.

Carefully mix in the flour and salt.

Pour/spoon the batter into your prepared pan and spread into an even layer. Bake in the preheated oven for about 23-28 minutes, or until the top is set and an inserted toothpick comes out clean or with a few moist brownie crumbs.

Cool in the pan on a wire rack before frosting.

Add the instant coffee to the boiling water. Whisk together with a fork to help dissolve the coffee. Cool fully - you can place the mixture in the fridge to speed up the process.

In a large bowl using a stand or hand-held electric mixer beat the butter for about 1 minute to soften.

Turn the mixer down to low speed and beat in 1 cup powdered sugar, along with the vanilla and salt.

Beat in the instant coffee dissolved in water. Make sure that the water isn't warm - otherwise it will melt the butter.

Beat in the rest of the powdered sugar about ½ cup at a time, until the desired sweetness and consistency is reached. If needed, beat in 1 tablespoon of cream.

Remove the brownies from the pan using the overhang of the parchment paper. Place on a cutting board. Frost the brownies using a flat-edge knife (be sure the brownies are fully cooled). Slice using a sharp knife.