First things first—preheat your oven to 350°F (175°C). That’s the ideal temperature for achieving that beautiful crust while keeping the inside gooey. While the oven is heating up, line an 8x8-inch baking pan with parchment paper. Don’t forget to leave some overhang for easy removal later!

In a medium bowl, whisk together the cocoa powder, flour, arrowroot powder, and salt. This step is crucial as it ensures that your brownies have an even texture. Mixing them together allows all the dry ingredients to mingle, creating a more uniform batter.

In a large mixing bowl, combine the softened butter and white sugar. Using an electric mixer, cream them together until the mixture is light and fluffy. This step typically takes about two to three minutes. Add the eggs and egg yolk, incorporating them well.

Next, you’ll want to pour in the brewed coffee and vanilla extract. The coffee brings out the chocolate flavor, making it richer, so don't shy away!

Gradually add the dry mixture into the wet ingredients, folding gently with a spatula. Don’t overmix; just combine until you see no more floury streaks. Then, fold in the semi-sweet chocolate chips for that extra chocolaty goodness!

Pour the batter into the prepared baking pan and spread it evenly. The batter will be thick, so don’t worry—this is exactly what you want.

Place the pan in the preheated oven and bake for about 25-30 minutes. You know they’re done when a toothpick inserted into the center comes out with a few moist crumbs. For that chewy texture, avoid overbaking.

Let the brownies cool in the pan for about 10 minutes. Then, using the parchment paper overhang, lift them out. Allow them to cool completely on a wire rack before cutting into squares. The wait might be tough—but trust me, it’s worth it!