01 - Preheat the oven to 350°F. Line a 12-cup muffin tin with cupcake liners.
02 - Place one whole Oreo cookie at the bottom of each cupcake liner.
03 - In a medium bowl, whisk together the all-purpose flour, unsweetened cocoa powder, baking soda, and salt until evenly distributed.
04 - In a large bowl, beat the softened butter and granulated sugar together using an electric mixer until light and fluffy, about 2 to 3 minutes. Add the eggs one at a time, mixing well after each addition.
05 - Mix in the buttermilk, vanilla extract, and red food coloring until fully combined and the color is uniform.
06 - Gradually add the dry ingredient mixture to the wet batter, mixing on low speed until just combined. Avoid overmixing.
07 - Divide the batter evenly among the prepared cupcake liners, filling each about three-quarters full to cover the Oreo cookie at the bottom.
08 - Bake for 18 to 20 minutes, or until a toothpick inserted into the cupcake center (avoiding the Oreo base) comes out clean. Transfer to a wire rack and let cool completely.
09 - In a mixing bowl, beat the softened cream cheese and butter together until smooth and creamy. Add the sifted powdered sugar and vanilla extract, then mix until light and fluffy. Gently fold in the crushed Oreo cookies until evenly distributed.
10 - Pipe or spread the cream cheese frosting generously onto the fully cooled cupcakes. Garnish with additional Oreo crumbs or mini Oreo cookies if desired.