Colouring The Ganache:
Chocolate seizes when it comes in contact with water. So for colouring chocolate oil based colours are used. But for this ganache, as we are adding the colours to the cream, you can use any food colour you want. I have used gel colour. You can also use liquid colours or powder colours. When using powder colours, add the colour with one or two teaspoon of warm water, mix thoroughly and then add it to the cream. Other wise you may end up with speckles in the final ganache.