Line your cupcake pans then set them aside.
In a large bowl using the hand mixer cream the butter, sour cream. vegetable oil, and granulated sugar until light and creamy.
Add eggs, and mix for about two minutes, then add the vanilla and continue to mix until all ingredients are fully incorporated.
In a separate bowl combine the flour, baking powder, baking soda, and salt. Give it a quick whisk, then set aside.
Start adding the dry ingredients to the wet ingredients in thirds, alternating with the buttermilk. Continue to mix until all ingredients ar incorporated.
Using a trigger release ice cream scoop, scoop the cupcake batter, and release onti the lined cupcake pan.
Bake at 350°F for about 8 to 10 minutes
Let the cupcakes cool down at room temperature in the pan for a few minutes, then transfer to a cooling rack.