Making Guinness Brownies is straightforward. Follow these easy steps to create your perfect batch:

1. Preheat Oven: Preheat your oven to 350°F (175°C). Grease and line a 9×13-inch baking pan with parchment paper.

2. Melt Butter: In a saucepan over medium heat, melt the unsalted butter. Once melted, stir in the Guinness stout and bring to a simmer.

3. Mix Sugars: Remove from heat and mix in granulated sugar and brown sugar until fully combined.

4. Add Eggs and Vanilla: Allow the mixture to cool slightly, then whisk in the eggs one at a time. Add the vanilla extract and mix well.

5. Combine Dry Ingredients: In a separate bowl, sift together the flour, cocoa powder, baking powder, and salt.

6. Combine Mixtures: Gradually add the dry ingredients to the wet ingredients, stirring until just combined. Be careful not to overmix.

7. Add Chocolate Chips: If desired, fold in the semi-sweet chocolate chips for an extra chocolatey experience.

8. Pour Batter: Pour the batter into the prepared baking pan, spreading it evenly.

9. Bake: Place the pan in the preheated oven and bake for 25-30 minutes. A toothpick inserted in the center should come out with a few moist crumbs.

10. Cool: Remove from the oven and let the brownies cool in the pan for about 15-20 minutes. Then, transfer to a wire rack to cool completely.