Melt the butter and 1 cup of the chocolate chips together in a double boiler or in the microwave on the chocolate setting in 20 second increments, stirring in between until smooth.
Stir in the sugars and salt, then the eggs, then the flour, stirring just until combined. Stir in the rice krispies - it will be pretty thick.
Spread the batter evenly in the prepared pan. Bake until a toothpick inserted in center comes out with moist crumbs attached about 35 minutes.
Remove the brownies from the oven to a wire rack and sprinkle the remaining chocolate chips over top. Wait 15 - 20 minutes then spread the melted chips gently over the top - they won't cover it completely - it's just to give the rice krispie layer something to adhere to. Let cool completely.