01 - Preheat the oven to 350°F (175°C). Line a standard 12-cup muffin tin with paper cupcake liners.
02 - In a medium bowl, whisk together the all-purpose flour, unsweetened cocoa powder, baking soda, and salt until evenly distributed. Set aside.
03 - In a large mixing bowl, beat the vegetable oil and granulated sugar until well combined. Add the room-temperature egg, buttermilk, red food coloring, pure vanilla extract, and distilled white vinegar. Mix until the mixture is smooth and uniformly red.
04 - Gradually add the dry ingredient mixture to the wet ingredients, mixing gently just until combined. Do not overmix. Gently fold in the roughly chopped Oreo cookies with a spatula.
05 - Divide the batter evenly among the prepared cupcake liners, filling each liner about two-thirds full to allow room for rising.
06 - Bake for 18 to 20 minutes, or until a toothpick inserted into the center of a cupcake comes out clean. Allow the cupcakes to cool in the muffin tin for 5 minutes, then transfer them to a wire rack to cool completely.
07 - In a medium bowl, beat the softened unsalted butter and softened cream cheese together using an electric mixer until creamy and lump-free. Add the sifted powdered sugar and pure vanilla extract, then beat on medium-high speed until the frosting is light, fluffy, and smooth. Gently fold in the finely crushed Oreo cookies.
08 - Once the cupcakes are completely cooled, pipe or spread the cream cheese Oreo frosting generously onto each cupcake. Garnish with additional Oreo crumbs if desired.