Preheat your oven to 350°F (175°C).
Grease a 9x9 inch baking pan.
In a large bowl, mix flour, sugar, cocoa powder, baking powder, and salt.
In another bowl, whisk melted butter, eggs, and vanilla until combined.
Pour the wet ingredients into the dry ingredients and stir until just combined.
Spread the batter evenly into the prepared pan.
Bake for 25 minutes or until a toothpick inserted comes out clean.
Let the brownies cool in the pan for 10 minutes.
Frost the brownies with chocolate frosting.
Top with colorful sprinkles before slicing into squares.