Creating the ultimate Chocolate Brownies is simple if you follow these clear steps:

1. Preheat Oven: Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking pan or line it with parchment paper for easy removal.
2. Melt Butter: In a medium saucepan, melt the unsalted butter over low heat. Remove from heat and let it cool slightly.
3. Mix Sugar and Eggs: In a large mixing bowl, combine the melted butter and granulated sugar. Mix well, then add the eggs one at a time, stirring to incorporate after each addition. Add the vanilla extract and mix until smooth.
4. Combine Dry Ingredients: In another bowl, sift together the all-purpose flour, unsweetened cocoa powder, baking powder, and salt.
5. Combine Mixtures: Gradually add the dry ingredients to the wet mixture, stirring until just combined. Do not overmix.
6. Add Extras: Fold in the semi-sweet chocolate chips and/or chopped nuts if desired.
7. Pour Batter: Pour the brownie batter into the prepared baking pan, spreading it out evenly.
8. Bake: Place the pan in the preheated oven and bake for 25-30 minutes. The brownies are done when a toothpick inserted in the center comes out with a few moist crumbs.
9. Cool: Remove from the oven and let the brownies cool in the pan for 15-20 minutes before transferring them to a wire rack to cool completely.
10. Cut and Serve: Once cooled, cut into squares and serve as desired.

These detailed steps will guide you in creating delicious Chocolate Brownies effortlessly.