hi yan perfect way to get bright white buttercream add a tiny bit of violet food colouring this blocks out the yellow and gives you white buttercream 🙂

Beat well with an electric mixer until light and fluffy. Add food coloring if desired.

For the swirl I have used the techniques from the Wilton site: https://www.cupcakefun.com/techniques/1mswirl.cfm and I use the 1M nozzle tip.

I know the problem of getting the bc “white” if you dont use shortning there is white. I have some super white powder from Sugar Flair that makes it a bit more whiter to the BC. But dont add it before the butter was very “light” in color.

You could also try make bc out of half butter, half shortning that maybe gives a more light bc?

I think that I have used a tiny bit of Wilton: Skye blue.

Hope that helps:)

Louise