Pre-heat oven to 350 degrees

In a large bowl, combined chopped bittersweet chocolate, cocoa powder and ¾ cup hot water. Whisk until smooth and all chocolate is melted. Place in the fridge to chill for about 30 minutes

In another large bowl, combine flour, sugar, salt and baking soda

When the chocolate mixture is cooled, whisk in 6 tbsp vegetable oil, 2 eggs, 2 tsp vinegar and 2 tsp vanilla extract

Combine the dry ingredients with the wet and whisk until all of the ingredients are incorporated together

Line cupcake pans with paper liners and place 1 oreo in the bottom of each liner

Pour batter over each cookie and fill each liner ¾ full. You should get about 18 cupcakes

Bake for 15 minutes or until toothpick comes out clean

Cool on a wire rack

While the cupcakes are baking, prepare the frosting. In a small sauce pan combine 5 tbsp all-purpose flour and 1 cup milk. Whisk constantly over medium-low heat until it becomes REALLY thick. Place in refrigerator or freezer until it is cooled completely

When the milk mixture has cooled, cream together butter, sugar and vanilla until creamy. Add in the milk mixture and mix on low for about 30 seconds. Then mix on high for about 3 minutes or until it becomes whipped cream like. Add in crushed Oreos and mix for about 30 seconds

Pipe frosting onto each cupcake and top with an additional cookie for garnish