Preheat the oven to 350, generously butter a 9 x 13 cake pan, line it with parchment and butter the parchment.  In a large glass bowl, microwave the butter and chocolate chips together in 30 second increments until just melted and smooth when stirred, then stir in the sugar, vanilla and instant coffee.

In a separate bowl, whisk the eggs vigorously for a good minute until frothy and then stir the eggs into the chocolate mix.  Add in the flour, cocoa and baking powder and stir until dry bits are no longer visible, then stir in the half cup of chocolate chips.

Scrape the batter into your prepared pan, smooth out the top and bake for about 25 to 28 minutes until the brownies are just set.  Leave them to cool completely if you’d like nice squares, but oh my goodness you really need to try one warm!