AI need to color smbc several different colors for a cake. The base of the cake is gray. The accents and borders are bright orange, lime green, and turquoise blue. I've never tried to color smbc before. Is achieving these colors going to be hard? I think I read somewhere that I can't use gel coloring because it will fade or color won't take. What about powdered colors? Any ideas or tips please! Tia!

AUse oil based/candy colorings. Smbc will have no whiteness power of ps cornstarch that abc does, to hold onto the color. Yellow base of butter will be more pronounced. I've read in the past some have luck heating a bit of the colored buttercream and beating it back in to help darken the tone. Be aware if you plan to use a hot /warm spatula to do your final smoothing the color will noticeably change. I don't do saturated colors in smbc, but I hope this helps. (I'd use a hybrid like Charlottes)

AGel color works good. For big batches it's easier to color the meringue as it takes the color better than the greasy butter. In that case powers work fine. But if it's small amounts stick to gel.

AThankyou.

Powdered colors also work well.  Crystal Colors [sugarpaste.com] uses pure color lakes, so for saturated colors, you don't use as much and they don't change the flavor or texture of the BC.