Preheat oven to 325°F. Place cupcake liners in muffin pans.
In a large mixing bowl, whisk together the sour cream, buttermilk, vanilla, orange liqueur, orange oil, eggs, and vegetable oil until smooth. Add a few drops of orange food coloring to make the batter a pale peach color. Then sift in the cake mix and stir until smooth but not overmixed. Do not skip sifting the cake mix; otherwise, the batter will be lumpy.
Using a cookie scoop, divide the batter evenly between the liners, or fill them 1/2 to 2/3 full.
Bake for 20 minutes or until cupcakes are lightly browned and a toothpick inserted into the middle comes out clean or with crumbs. Do not overbake. After 5 minutes, move the cupcakes to a cooling rack. Cool before frosting.
Orange Buttercream Frosting
Use an electric mixer to beat the butter, vanilla, orange oil, and salt until creamy.
Add the whipping cream to the butter and beat until mixed. Then add the powdered sugar one cup at a time, beating between each addition. If the frosting is too stiff, add more cream. Add a little orange gel coloring and beat. The color should be a pale peach color.
Use a piping bag and a large star tip to pipe frosting onto the cupcakes. Make a circle of frosting around the outside of the cupcake top, then continue circling, moving in closer to the middle with each circle. This will make the frosting taller in the middle of the cupcake. Alternative: Use less frosting on each cupcake, start piping in the middle, then make circles moving to the outside with each circle. This method will make a "rose" shape on each cupcake.
Add sprinkles to each cupcake for decoration.
Notes
Substitution
One half a teaspoon of orange essential oil is equivalent to one tablespoon of orange zest.