Instructions

1. Preheat the oven to 350°F (175°C). Grease a 9x13-inch baking dish.

2. Melt the butter in a large saucepan over low heat.

3. Add the sugar and stir until combined. Remove from heat.

4. In a separate bowl, beat the eggs until light and frothy. Add the eggs to the saucepan with the sugar mixture and stir until combined.

5. Add the cocoa powder, salt, baking powder, espresso powder, and vanilla extract to the saucepan and stir until well combined.

6. Add the flour and chocolate chips to the saucepan and stir until just combined.

7. Pour the batter into the prepared baking dish and bake for 25-30 minutes, or until a toothpick inserted in the center comes out clean. Let cool before serving.