I have a horrible time coloring buttercream red so now would like to purchase a pre-made red colored buttercream. Which company makes the truest red color?

thanks

This works well unless you want to cover a whole cake with red: buy a tube of Wilton's red. Cut the back off the tube & scrape it out. Now mix that w/1/3 cup of pink, or orange, or yellow b'cream of your own. That Wilton red is SOOOOOOOO color saturated(sp?) it will come out just right. If the color you add it to is deep enough - not a pale, pastel shade it will be fine.
The tubes are small - just a couple of tablespoons worth but most of the time you only need a small amount of red .

The other thing I do when needing a lg amount is to tint the white icing as mentioned above, a deep pink, yellow or orange, then add red gel. When it is close to what you want, add about 1/4 to 1/2 teaspoon UNsweetened Kool Aid powder (I don't measure it, just add some depending on how much I think it needs to darken/color). I prefere using Black cherry but any read flavor will work. Let the icing sit overnight (or simular time). When you go to use it, it might have dark speckles so just stir up well and it will be fine.

If you are going to be piping the buttercream, you do NOT colour it the final depth. Colour it a medium shade and let it sit overnight.

Use the Wilton method: brush a solid coat of undiluted paste colour straight from the bottle all over the inside of the icing bag after the tip is in place. When you pipe, the colour on the outside will be intense.