Preheat your oven to 350°F (175°C). Prepare an 8-inch baking dish by greasing it with non-stick spray or lining it with parchment paper and then spraying it with non-stick spray for easy removal.

In a microwave-safe bowl, melt the butter in the microwave. Be sure to check every 15 seconds to avoid overheating.

In a large bowl, combine the melted butter, sugar, eggs, vanilla extract, and coffee extract. Mix until well combined, ensuring the eggs are fully incorporated.

Add the cocoa powder, flour, salt, and baking powder into the wet ingredients. Stir until everything is well combined, making sure there are no lumps.

Spread the batter evenly into the prepared baking dish. Bake for 35 minutes or until a toothpick inserted in the center comes out clean.

Allow the brownies to cool completely before preparing the frosting. This step is crucial as it prevents the frosting from melting.

Dissolve the instant coffee in the heavy cream and set it aside. In a large bowl, beat the butter until light and fluffy, about 3-5 minutes.

Gradually add the powdered sugar, mixing until smooth. Incorporate 2 tablespoons of the coffee-infused cream into the frosting and mix well. Add more cream, 1 tablespoon at a time, until you reach your desired frosting consistency.

Frost the cooled brownies generously, slice them into squares, and indulge in these delightful coffee-infused treats!