Preheat oven to 350°F. Line a 12 cup muffin tin with muffin liners. Set aside.
In a large mixing bowl, sift the flour, cocoa powder, baking soda, and baking powder. Then, add in the sugar and salt. In a separate bowl, mix the buttermilk, oil, vanilla, and eggs.
Pour the wet ingredients into the dry ingredients. Whisk until combined. Heat the water on the stove until steaming. Slowly mix the hot water into the batter.
Use a 3 oz cookie scoop to scoop the batter. Fill the muffin liners ¾ full. Bake for 22-25 minutes. They are done baking when a toothpick inserted comes out clean.
Let the cupcakes sit in the pan for 10 minutes. Then, transfer to a cooling rack. Cool completely before filling and decorating.
Whipped Oreo Cream Cheese
Use a food processor or crush the Oreos in a sandwich baggie. There should be small and medium sized pieces. Place a metal bowl and whisk attachments in the freezer for 10 minutes.
Beat the cream cheese on high for 1 minute. Add in the vanilla and sifted powdered sugar. Mix on low until combined. Beat on high until smooth.
Pour heavy cream in the cold bowl and beat on high until stiff peaks form. Pour whipped cream into the cream cheese mixture. Fold gently until combined and no cream cheese streaks remain.
Remove ¼ of the whipped cream cheese. We won't need that much. Fold in the crushed Oreos into the ¾ whipped cream cheese.
Use a cupcake corer or a sharp knife to cut a hole in the cupcakes about ⅔rds down. Toss the filling and tops. Fill the cupcakes to the top with whipped cream cheese.
Oreo Cream Cheese Frosting
Set the butter on the counter for 30 minutes to get slightly cold. Sift the powdered sugar while you wait. Use a food processor to blend both Oreos into fine crumbs. Pour Oreo crumbs in with the powdered sugar.
Using a mixer, beat the butter and room temperature cream cheese. Beat on high for 2-3 minutes until light and fluffy. Scrape the bowl.
Slowly add in the powdered sugar/Oreo crumbs. Mix until combined. It will be thick. Add in vanilla and heavy cream. Beat on low until combined. Switch to high and beat for 2 minutes. It should be light and fluffy. Pipe the cupcakes. I used a 1M wilton tip. Keep cupcakes in the fridge.
Flour- Make sure flour is spooned and leveled or use a kitchen scale. Compacted flour can dry out the cupcakes.High altitude baking- Add an extra 1 tablespoon of flour.Make sure all "room temperature" ingredients are pulled 2 hours before baking.