In the bowl of a stand mixer on medium speed, beat together butter, oil and sugar until thoroughly combined
About three minutes.
Add the eggs one at a time and mix well after each addition.
Add half the dry ingredients and mix well, then add half of the soured milk mixture.
Add the rest of the dry ingredients and mix well, then add the rest of the soured milk mixture
Scoop the batter with an ice cream scoop into muffin cups.
Bake the cupcakes for 25-30 minutes.