A brownie is a fudgy, rich, dense baked bar with cocoa powder or melted chocolate, while a "blondie brownie" has a buttery, caramel/butterscotch flavor.
You'll only need a few simple ingredients to make this easy recipe. Let's round them up and get started!
Mix together the butter, granulated sugar, brown sugar, eggs, vanilla, salt, baking soda, flour, coconut, chocolate chunks, and marshmallows.
Spread the batter evenly into the prepared pan and bake for 25 minutes. The edges will be golden and the center will just be set.
Allow the bars to cool completely in the pan before cutting into bars.
Sprinkle with flaked sea salt if desired, and dig in.