Preheat the oven to 350°F (175°C). Line a 9x9 inch baking pan with parchment paper, leaving some overhang for easy removal.

In a mixing bowl, whisk together the melted butter and sugar until combined. Add the eggs and vanilla extract, mixing until smooth.

In a separate bowl, combine cocoa powder, flour, salt, and dissolved coffee granules. Gradually add the dry ingredients to the wet ingredients, stirring until just combined.

Pour the brownie batter into the prepared baking pan, spreading it evenly. If desired, sprinkle chocolate chips on top.

Bake in the preheated oven for 25 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.

Allow the brownies to cool in the pan for about 10 minutes, then lift them out using the parchment paper. Let them cool completely on a wire rack before cutting into squares.

Dust with espresso powder before serving, if desired.