Preheat oven to 350 degrees. With a stand or hand mixer, cream together the butter and sugar until fluffy. Add the egg and vanilla and mix until combined.
In a separate bowl, sift together the flour, cocoa, salt and baking powder. Gradually add the dry ingredients to the wet. Mix until the dough is completely combined.
In a separate bowl, sift together the flour, cocoa, salt and baking powder. Gradually add the dry ingredients to the wet. Mix until the dough is completely combined.
Cut the refrigerated dough into 18-24 even cubes. With your hands roll the cubes into balls. Roll the balls in the mini chocolate chips and place on an un-greased cookie sheet.
Lastly, press a Rolo candy into the top of each ball. Bake for 9-10 minutes, and cool on the cookie sheet for 3-5 minutes before removing the cookies from the sheet.