In a large bowl, beat butter and cream cheese at medium-low speed until smooth and creamy, about 1 minute. Beat in vanilla. Reduce mixer speed to low, and gradually add confectioners' sugar, beating until combined. Increase mixer speed to medium, and beat until fluffy, about 1 minute.
Recipe by Bake from Scratch at https://www.bakefromscratch.com/red-velvet-thumbprint-cookies/