Preheat oven to 190°C/fan 170°C/gas mark 5.
Grease and line a swiss roll tray. Place Fate Low Protein Chocolate Flavour Cake Mix into a mixing bowl. Add the margarine and the water and using an electric whisk, mix well for 1 minute.
Pour mixture into swiss roll tray and bake for 12 - 15 mins until risen and firm.
Remove from oven and immediately turn it out onto a piece of greaseproof paper (the paper that was used to line the tray may still be on the cake, so remove this, and throw it away).
Spread cake with jam, and whilst it is still hot, gently roll it up, starting at the longest side, using the greaseproof paper to help you.
Roll up tightly and place it on a wire rack or plate to cool.
Place the swiss roll on a cake board and trim both ends to neaten.
Gently spread the chocolate icing or melted Vitabite over the whole of the cake to cover. Grate the Vitabite and sprinkle over the cake.
Lightly dust work surface with icing sugar. To make the caterpillar face, cut out a circle of the orange icing and gently press onto the front of the swiss roll.
Add a Skittle for its nose securing using a dab of the cake topping. Make the eyes by cutting out circles from the black and white icing and the eyebrows by rolling out a small strip of black icing, use a dab of water to place these on the face.
Use the pointed end of a knife to draw the shape of a mouth into the icing.
For each antenna roll a small amount of red icing narrowing at one end and place on top of the face with a dab of water.
The caterpillar can then be decorated with Skittles and hundreds and thousands/sprinkles (legs can be added with small strips of red icing if desired).
Fate Low Protein Chocolate Flavour Cake Mix and Vitabite are foods for special medical purposes and must be used under medical supervision. These recipes have been specifically designed for use in a low protein diet.
Refer to labels for allergen and other product information.