I used to encounter the same problem since I’m from a country that has a very warm weather..yes you can put shortening and confectioner’s sugar to stabilize your buttercream icing.hope this will help :)
https://www.facebook.com/media/set/?set=a.316152991730539.86035.316152381730600&type=3#!/pages/Pearlees-Cakes/316152381730600
