I have made this for over forty years without the water, only beating with a mixer the rest of the ingredients... no need to cook on stove...

This was a great frosting. Only thing I did differently was used salted butter and did not add any salt. Also, used butter flavored shortening. And used a little less than 1/2 a cup of water (because I wanted it to be a little stiff for making roses.) It tasted great. A total crowd pleaser. BTW-if you want a little different taste, use french vanilla clear extract instead of just regular vanilla. It's a little different.

I also rearranged the butter/shortening ratio, limited the salt to 3 "shakes" and the milk to 3 tablespoons (only because I was adding coloring to the frosting.) Almost sounds like a new recipe! However, after all the adjustments, it produced a very pretty and stiff icing for decorating.

I made this recipe . . . as directed. Tasted great! Very easy and fun to decorate with. I made an Easter Bunny cake and it looked fantastic. Frosting was easy to work with, not too heavy, not too moist and not too sweet. A lot of frosting was made, had plenty leftover for kids to dip "cake scraps" into. Would make this again.

This recipe was very similar to another I had found, except the other called for milk, which I used. I liked the frosting, but ALL the grandkids did not (scraped off the frosting), and my daughter thought it was the "shortening taste." So I turned the butter and shortening around (1 c. butter and 1/2 c. butter flavored shortening) and went back to water (I remembered my mom using water and not milk), and the kids LOVED the last cake I made, frosting and all.

I took Mary M's suggestion, and I think 1/2 tsp of salt is WAAYYY too much! You should not be able to taste the salt as much as I did, and I used salt-free butter. I think 1/4 should be enough. And I don't think you need to blend the first four ingredients for 3 minutes, about a minute and 1/2 was perfectly fine, but I blended for 2, just to be sure.
I added another 2 cups of powdered sugar, and another 2 tablespoons of water. It was then perfect with the 1/2 tsp salt.
All in all, with all the modifications I had to make with this recipe, I would not recommend it.