Delicious chocolaty soft brownies, topped with nuts and marshmallows and yes mini rolos!
Preheat oven to 350 F.
Lightly grease an 8 inch square pan.
Combine butter and cocoa in a medium sized saucepan, and heat over low heat, stirring constantly until smooth. Remove from heat and whisk in sugar, egg, flour, buttermilk and vanilla. Mix until smooth.
Pour batter evenly into prepared pan. Bake for 25 minutes, check with a toothpick as soon as the centre is dry. Do not over bake.
Remove from oven and sprinkle with marshmallows, walnuts and rolo pieces. Return to oven for 3-5 minutes, until it starts to meld together. You may want to broil for a minute, tops, to get that golden brown. Careful not to burn it.
Cool in the baking pan on a wire rack. Once cool, cut into 2 inch squares.