Dunkin Donuts Coffee Coolatta is the ultimate iced coffee. It's not, as some people would have you believe, a coffee milk shake, and it doesn't contain any ice cream. A real Dunkin Donuts Coffee Coolatta contains Dunkin Donuts coffee and frozen Dunkin Donuts coffee, with sugar and milk to taste. While it's not an exact match for a store bought Coffee Coolatta, you can make your own version of a Dunkin Donuts Coffee Coolatta at home if you plan ahead just a little bit.
Brew a pot of Dunkin Donuts coffee. Dunkin Donuts coffee is sold by the pound at all Dunkin Donuts stores. It's also available at many supermarkets, or online through the Dunkin Donuts web site. I prefer to buy it in whole bean form so I can grind it myself just before I brew a pot of coffee.
Pour half the pot into an ice cube tray and freeze it. If you cover the tray with a sheet of plastic wrap, you can avoid the ice picking up any other flavors from the freezer.
Pour one cup of Dunkin Donuts coffee into a cup with a cover and put it in the refrigerator to cool. I generally do this every morning when I make the first pot of coffee for the day. I get a fresh, hot coffee to start my morning and split the rest between the freezer and the fridge.
When the coffee cubes are frozen, remove them from the ice cube tray and drop them into a blender. One full tray of coffee cubes is just about right to make a large Coffee Coolatta.
Add one cup of chilled coffee and sugar to taste to the blender and cover. Pulse the coffee cubes and coffee to break up the cubes into small chunks. Switch to high speed on your blender and whirl for 1 to 3 minutes or until the ice and coffee are the consistency of slush.
Pour the Coffee Coolatta mixture into a tall glass. Add light cream, whole milk or skim milk if desired. Top with whipped cream if desired.