Preheat your oven to 350°F (175°C).

Prepare your baking pan by greasing a 9x9-inch baking pan with butter or cooking spray.

In a large mixing bowl, whisk together the dry ingredients: flour, sugar, cocoa powder, baking powder, and salt.

In another bowl, mix the wet ingredients: melted butter, eggs, and vanilla extract until smooth.

Combine the wet and dry ingredients, stirring gently until just combined.

Pour the batter into the prepared baking pan and spread evenly.

Bake for 20-25 minutes, checking for doneness with a toothpick.

Allow the brownies to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before cutting into heart shapes.