Sift together cocoa, flour, baking soda, and salt into a bowl and set aside.
Cream together the butter and both sugars with electric mixer for about 2 minutess or light in color. Add the eggs into the mixture one at a time. Now add the vanilla and mix well.
Now you will add the dry mixture into the mix 1 cup at a time, making sure the dry is completely mixed in before adding another cup.
Stir in the chocolate chips and toffee evenly throughout the dough.
Now line a cookie sheet with either a silicone baking mat or parchment paper and drop the cookies by spoonfuls onto the sheet. I would keep them at least 1 1/2 to 2 inches apart. Bake for 12 to 14 minutes.