Using a stand mixer, cream together the butter and sugars until light in color and fluffy in texture.
Add in the eggs, corn syrup and vanilla. Mix until thoroughly combined.
Next, add the flour, cocoa, cornstarch baking soda and salt. Mix until your chocolate cookie dough forms. The dough will be soft.
Divide the dough out into 12 equal portions, I like to use my 1/2 cup measuring cup to help divide the dough. You'll want to use a little less than 1/2 cup of dough to have 12 cookies.
Roll each portion onto a ball then flatten slightly so it looks like a hockey puck before arranging on a parchment paper or silicone mat covered pan. Place 6 cookies per tray.
Bake at 350° for 15-17 minutes. The cookie should start to crack and crinkle, it will spread slightly and the centers of the cookie should no longer look wet before taking them out of the oven.
While the cookies are baking in the oven, make the fudge frosting by measuring out the heavy cream into a microwave save bowl.
Microwave the cream for 1 1/2 minutes or until it is boiling.
Remove the bowl from the microwave and add in the chocolate chips. Use a spoon and push the chocolate chips around so they are all covered by the heavy cream.
Allow the chocolate chips to sit in the hot cream for 3 minutes.
After the 3 minutes is up, use a whisk and stir the chocolate chips into the heavy cream until smooth. Set aside and let it cool while the cookies finish baking.
Once the cookies are out of the oven, let them cool on the pan for about 10 minutes and then spoon the frosting onto the top of each cookie and sprinkle with the candy coated chocolate chips while the icing is still wet.
Cookies store really well in the fridge and can be made a few days in advance if needed.