Every time I try to make my own butter cream frosting using the Wilton recipe I fail miserably! It ends up super watery or tasting more like a whipped icing instead. I'm doing it exactly as the recipe says. And then when I add color it starts to all separate. But I don't have any issues with the box of wilton butter cream mix.

Any ideas on what I possibly could be doing wrong??

I tweaked my buttercream recipe for years until I found one I liked. Try some of the recipes here on CC like Indydebi's buttercream until you find one you like:

http://cakecentral.com/recipes/6992/indydebis-crisco-based-buttercream-icing

Which recipe are you using? Can you type it out in here?

There are so many icing recipes out there, if one isn't working for you I would just try another. I hear SugarShack and Tonedna have very good ones. I like IndyDebi's myself. My hubby who does not like frosting will eat that stuff with a spoon right out of the mixer! There is also another one that I can't remember the name of (it's in my faves though, I'll check) it used shortening, half unsalted butter and half salted butter. I tried it the other day and I did like the more buttery flavor of it.

Here's the recipe I was referring to earlier:

http://cakecentral.com/recipes/2123/buttercream-dream

I use the Wilton buttercream recipe except I use hi-ratio shortening instead of Crisco. I think it makes the icing so much smoother and easier to work with.

One thing I did learn about coloring icing, do not use a mixer, use a spoon. It takes a while longer, but in my experience it keeps the icing from separating.

HTH

Kim