On the stovetop, in a saucepan, stir the BAKER'S Unsweetened Chocolate and the butter on low until the chocolate and butter are melted completely and the mixture is smooth. Remove from heat and set aside to cool.
Preheat oven to 350 degrees F. Cover a 9x13 inch baking dish with tin foil being sure to cover the edges (this just basically makes clean up a LOT easier since you're using marshmallows and caramel). Grease the foil and set aside.
Return to the cooled chocolate mixture and stir in the sugar.
Add each egg one at a time beating in just until each egg is combined.
Add the vanilla.
In another small bowl, mix together the flour and the baking soda.
Combine the dry ingredients with the wet ingredients and stir just until combined. The mixture should be pretty thick and still a bit lumpy.
Stir in the chopped BAKER'S Semi-Sweet Chocolate.
Pour and spread the batter into the prepared baking pan evenly.
Bake at 350 degrees for 20 to 25 minutes or until edges are set and center is almost set.
Remove from oven and top the brownies with sliced JET-PUFFED Pumpkin Spice Mallows make sure there is a fairly even layer.
Return to oven for about 5 minutes or until marshmallows are completely melted (and kinda look like a huge hodge podge mess on top).
Remove from oven.
In a microwave safe bowl, add the KRAFT Caramel Bits and the heavy whipping cream and microwave in 20 second intervals stirring after each time until melted and smooth.
Spoon and drizzle the caramel across the top of the brownies while still warm.