1. Preheat the oven to 350°F and line a 12-cup muffin pan with cupcake liners.

2. In a medium bowl, whisk together the flour, cocoa powder, baking soda, and salt.

3. In a large bowl, beat the granulated sugar and vegetable oil until combined, then mix in the egg, buttermilk, vanilla extract, red food coloring, and white vinegar.

4. Add the dry ingredients to the wet ingredients and mix just until a smooth batter forms.

5. Divide the batter evenly between the cupcake liners, filling each about two-thirds full.

6. Bake for 18 to 22 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.

7. Let the cupcakes cool in the pan for 5 minutes, then transfer them to a wire rack to cool completely.

8. Beat the softened butter until creamy, then gradually mix in the powdered sugar, vanilla extract, and enough heavy cream or milk to create a fluffy frosting.

9. Pipe or spread the frosting over the cooled cupcakes.

10. Top each cupcake with Oreo halves and a sprinkle of crushed Oreo crumbs before serving.