Begin the recipe by preheating the oven to 350 degrees F. and line a muffin pan with muffin liners and set aside.
In a small bowl, whisk together the ⅓ cup plus 1 tablespoon all-purpose flour, 2 teaspoons cocoa powder, ⅛ teaspoon baking soda, and ⅛ teaspoon salt. Set aside.
In a separate small mixing bowl, add in the ¼ cup canola oil, ¼ cup granulated sugar, 2 tablespoons buttermilk, and 1 large egg white. Use an electric mixer to mix these ingredients until combined.
Add in the 1 teaspoon red food coloring, ⅛ teaspoon white vinegar, ¼ teaspoon vanilla extract, and continue mixing until the cupcake mixture comes together and is creamy and smooth.
Now slowly add in the flour mixture a little at a time while continuing to mix until fully combined.
Pour the cupcake mixture into the prepared muffin pan. Fill the muffin liners with the batter until they are about ¾ full.
Place the muffin pan into the oven and bake for about 15 to 20 minutes or until a cake tester comes out clean. Allow the cupcakes to cool in the pan on a baking rake for 5 minutes before removing them from the pan to cool completely before frosting.
To make the frosting, in a small mixing bowl using an electric mixer, add in the 3 ounces softened cream cheese, 2 tablespoons softened butter, 1 teaspoon buttermilk, 6 tablespoons powdered sugar, and ¼ teaspoon vanilla extract until combined and smooth.
If you would like a thicker frosting, then add in more powdered sugar and if you would like a thinner frosting, then add in more buttermilk until the frosting reaches the consistency that you prefer.
Frost the cupcakes and enjoy. Store the red velvet cupcakes in an airtight container or plastic bag. They are fine to store at room temperature, but I prefer to keep them in the refrigerator for up to 4 days.