Preheat your oven to 350 °F (about 175 °C) and prepare an 8‑inch baking dish by spraying with non‑stick spray or lining with parchment paper then spraying.

In a microwave‑safe bowl, melt the butter.

In a large bowl, combine the melted butter, granulated sugar, eggs, vanilla extract and coffee extract/instant coffee. Stir until well‑combined.

In a separate bowl (or add directly) mix the cocoa powder, flour, salt and baking powder. Add the dry ingredients into the wet mixture and stir until just combined.

Spread the batter evenly into the prepared pan. Bake for 30‑35 minutes—or until a toothpick inserted in the center comes out with a few moist crumbs (not raw batter).

Allow the brownies to cool completely in the pan. While they cool, prepare the frosting: mix the instant coffee granules into the heavy cream and set aside.

In a large bowl, beat the butter until light and fluffy. Slowly add the powdered sugar, mixing well — then add about 2 tablespoons of the coffee‑cream mixture and mix. Add more cream (1 tablespoon at a time) until you reach the desired frosting consistency.

After the brownies have fully cooled, gently spread the coffee frosting across the surface in an even layer. Slice into squares and enjoy!