• Preheat oven to 350 degrees Fahrenheit (375˚F for high altitude). Line muffin tin(s) with paper cupcake liners.
• *Prepare Oreos. Place 18 Oreo cookies in a food processor or blender and pulse 10 times. Remove 3/4 cup of the larger chunks for the cake batter, then pulse the remaining cookies until fine crumbs, which should equal to 1 cup. Set aside the fine crumbs for the frosting.

FOR THE CUPCAKES:

• Sift together the flour, baking powder and salt into a bowl with a fine mesh sieve. Set aside.
• In a separate large bowl, whisk together the oil and sugar.
• Add the eggs one at a time, whisking well after each one. Then add the vanilla and mix until incorporated.
• Add HALF of the dry ingredients. Mix until just combined.
• Add ALL of the buttermilk. Mix until combined.
• Fold in the remaining dry ingredients and crushed Oreo pieces until just combined. Do not over mix!
• Scoop batter 2/3 full (with a #24 scoop) into prepared cupcake pans (about 15 cupcakes). Do not over-fill.
• Bake at 350˚F (or 375˚F for high altitude) for 15-20 minutes until a toothpick inserted into the center comes out clean or with a few moist crumbs. Allow cupcakes to cool completely.

FOR THE FROSTING:

• Cream the butter in a bowl with an electric mixer until light and fluffy.
• Add the powdered sugar 1/2 cup at a time, mixing well after each addition.
• Add the vanilla and fine Oreo cookie crumbs. Mix until combined.
• Fit a piping bag with a large cupcake tip (like a Wilton 1M or 1A). Add the frosting and pipe onto each cupcake. Insert one Oreo cookie into the frosting of each cupcake for decoration.