Step 1
Preheat the oven to 180°C/fan oven 160°C/Gas Mark 4. Place 9 paper muffin cases into a muffin tin.
Step 2
In a large mixing bowl, beat together the Trex and sugar until light and fluffy. You can do this by hand with a wooden spoon, or use a hand-held electric mixer. Gradually beat in the eggs. Stir in the vanilla extract and milk.
Step 3
Sift the flour and salt into the mixing bowl, then gently fold them into the mixture using a large metal spoon. Spoon the mixture into the paper cases. Transfer to the middle shelf of the oven and bake for 20-22 minutes, until risen and golden. Cool in the tin for a few minutes, then transfer to a wire rack to cool completely.
Step 4
To make the icing, beat the butter in a bowl until smooth and creamy. Gradually sift in the icing sugar, beating well between each addition. Beat in the low fat soft cheese. Split the topping into 3 batches, mixing 2-3 drops of food colouring into each batch. Pipe or spread on top the cakes.