Toast black sesame seeds in a pan for about 30 seconds until you can smell a toasted black sesame aroma and they start popping. Pour into a spice grinder and pulse until it becomes very fine.
Preheat oven to 325F. Fill a cupcake baking pan with cupcake liners.
In a medium mixing bowl, add the flour, black sesame, baking powder, baking soda and salt. Whisk ingredients together to combine. In a measuring cup, add the milk and vinegar and whisk to combine.
In the bowl of a stand mixer fitted with paddle attachment or with a hand-held electric mixer and large mixing bowl, cream the butter, oil and sugar together until mixture appears thick and fluffy in appearance, about 2-3 minutes.
Beat the eggs into creamed butter mixture one at a time allowing the initial egg to be fully incorporated before mixing in the next egg. Next, mix in the vanilla extract into wet batter.
Reduce mixer speed to low. In an alternating fashion, starting and ending with the flour mixture, mix half of the flour mixture into wet batter, followed by all of the milk-vinegar mixture and ending with the remaining flour mixture. Mix until combined.
Scoop cupcake batter into prepared cupcake pans and bake for 18-20 minutes. Cupcakes are ready when a toothpick inserted into one of them comes out clean.
Cool cupcakes in baking pan for 4-5 minutes before transferring to a cooling rack to cool completely to room temperature.
To make the frosting:
Crush the Oreos in a food processor or by placing them in a plastic bag and smashing them with a rolling pin. Place the Oreo crumbs into the powdered sugar and whisk until combined.
Using a mixer, beat the butter and cream cheese. Beat on high for 2-3 minutes until light and fluffy. Scrape the bowl.
Slowly add in the powdered sugar and Oreo crumbs. Mix until combined. It will be thick. Add in vanilla and milk. Beat on low until combined. Switch to high and beat for 2 minutes. It should be light and fluffy. Pipe onto the cupcakes. Top with extra Oreo's.
Notes
Keyword Black Sesame, Cookies and Cream, Cupcakes, Oreo