Shortbread Recipe On Cornstarch Box : Melt In Your Mouth Shortbread Recipe Allrecipes : It used to be in the back of the cornstarch box, but since they changed to plastic packag… | / thanks for a nice winter recipe!. Cornstarch can almost always be replaced. Add some chocolate chips or lemon zest if you're feeling fancy. Shortbread is a holiday staple. She found the canada cornstarch shortbread cookie recipe and quickly baked up a batch, already knowing this had to be the one. In my mind shortbread contains butter flour and sugar in the proper proportions.