Preheat oven to 375ºF.
In a mixing bowl with a hand mixer or the bowl of a stand mixer fitted with the paddle attachment, mix the butter, shortening and confectioner's sugar on medium speed until light and fluffy, about 1 minute. Add the egg and extracts to the bowl, and mix to combine, scraping down the sides and bottom of the bowl.
Turn the mixer speed down to low and gradually add the flour and salt to the bowl, mixing until incorporated, about 30 seconds. Turn the mixer off, scrape down the bottom and sides and divide the dough in half. Remove one half of the dough from the bowl and add the red food color to the remaining half. Mix or knead it in until the color is blended into the dough evenly.