Colouring buttercream

[Greentomatoes21]

Not a big cake maker but always try to do my kids' birthday cakes. Just trying to a superhero cake with a mixture of red and blue buttercream. I used tescos own food colouring, new bottles opened today. Well, the blue is a nasty blue/grey and the red is like a brick/browny red. I had to use a lot of red to get any depth at all. Definitely not vibrant superhero tones. I ended up chucking them and will go with chocolate and some decorations - but for the future, does anyone know why I ran into this problem??

Supermarket food dyes are too watery. Get something like these next time:

Wilton 8 Gel Icing Colour Set, 226.4 g

You only need a tiny amount for really vibrant colours.

Also I think putting a few drops of lemon juice in makes the butter icing less yellow and more white.

You need to use gel colouring.

And whip the butter hard for a good 5-10 mins to make sure it is pale before adding icing sugar to it.

Definitely gel colouring, also as someone who makes cakes professionally red is my least favourite colour buttercream to make, it’s worse than black.

Make it as red as you can without ruining the texture, transfer into an airtight container and let the colour intensify, re mix when ready to use.

Would strongly recommend avoiding it all together though and opting for another option, good luck!

Thanks so much everyone!

Agree with everyone else - I got a set of Wilton cake gel colouring pots and haven't looked back. I even did a fantastic rainbow cake for my daughters last birthday, I was super pleased with such lovely vivid colours