Beat butter at medium speed with an electric mixer until creamy; gradually add powdered sugar, beating until blended. Add cream and oils, beating until smooth.
Divide mixture in half; color 1 half with green food coloring and the other half with red food coloring. Set 2 tablespoons pink mint mixture aside.
Roll mint mixtures to 1/4-inch thickness on wax paper. Cut with assorted 1-inch Christmas cutters. Place on wax paper-lined baking sheets. Roll reserved pink mixture into tiny balls; press onto holly leaf-shaped mints to resemble berries. Let stand 6 hours or until firm.
Spoon frosting into a small heavy-duty zip-top plastic bag. Snip a tiny hole in 1 corner of bag, and decorate mints as desired. Let stand 1 hour or until firm. Store in an airtight container.