For Brownies

1. Pre-heat the oven to 350 degrees Grease and line a 8 x 8 square baking pan with parchment paper. Let the paper slightly overhang the sides. Set aside.
2. Whisk together the flour, espresso powder, baking powder and salt. Set aside.
3. Put the butter and sugar into a medium-sized saucepan. Heat, over medium-low while whisking often, until the sugar is dissolved and the mixture shiny and smooth.
4. Do not allow it to bubble or foam. If you have a candy thermometer, you can tell it is ready when it registers at 50 Celsius.
5. While the butter mixture is melting over the stove, whisk the eggs, cocoa and vanilla in the bowl of a stand mixer fitted with the whisk attachment until it is glossy and flows like lava, about 2 minutes. Set the mixer speed on medium and slowly stream in the melted butter mixture. Whisk until evenly combined.
6. Pause mixing and sift over the dry ingredients. Again, whisk until just combined. Do not over mix.
7. Remove the bowl from the stand mixer. Use a large wooden spoon or rubber spatula to fold in the chocolate chips until evenly incorporated throughout the batter. Pour the mixture into the prepared baking pan and use an offset spatula knife to smooth and level out the top.
8. Bake for 25 minutes, or until the brownie is firm around the edges and just set in the middle. A wooden skewer inserted into the middle should not come out clean but with a few moist crumbs remaining.
9. Remove the pan from the oven and allow the brownie to cool completely. Once cool, coat the top of the brownie with the salted espresso frosting before sprinkling with salt.

For Frosting

1. First, melt down the chocolate. Place the chocolate into a medium-sized heat-proof bowl set over a saucepan filled with a few inches of barely simmering water. Do not let the bottom of the bowl touch the water below. Heat, over medium-low and stirring often, until melted and smooth.
2. Remove from the heat and set aside to cool slightly.
3. Meanwhile, in the bowl of a stand mixer fitted with the beater attachment, beat together the butter and sugar on medium speed until pale and fluffy, about 4 minutes. Set the mixer speed to medium-low and slowly stream in the melted chocolate.
4. Return the speed back to medium and beat until well combined, a further 2 minutes. Beat in the cream, cocoa, espresso, and vanilla until incorporated. Increase the mixer speed to medium-high and beat for a further minute, or until the frosting is lightened in colour, smooth, and aerated.
5. When you’re ready to frost the cooled brownies, use an offset palette knife or the back of a metal spoon to thickly spread the frosting over the top of the brownie.
6. I like to chill the brownie for about half an hour to slightly set the top so it’s easier to cut, but, you could serve the brownies immediately.