- Preheat oven to 190°C/fan 170°C/gas mark 5
- Rub the Fate low protein all-purpose mix and the margarine together in a mixing bowl until it resembles coarse breadcrumbs.
- Mix the sugar into the water until dissolved and combine with the Fate mixture.
- Leave to rest for 10 minutes.
- Dust a clean work surface with Fate low protein all-purpose mix and knead the pastry for a minute on the work surface until smooth.
- Roll the pastry out with a rolling pin to a 32cm circle and lift into the 26cm baking tin making sure that you press the edges.
- Leave to stand for 5 minutes.
- Cut the excess pastry off the sides.
- Make Fate chocolate cake mix up to packet instructions.
- Melt Vitabite in a heatproof bowl over a pan of boiling water.
- Add the Vitabite to the mixture and mix well.
- Fold in marshmallows until combined.
- Pour mixture into the pastry case and spread until level.
- Bake for 30 minutes.
- Remove from the oven and tin and allow to cool.
- Top with ProZero Double ‘Cream’ to serve.
Fate low protein all-purpose mix, Fate chocolate cake mix, ProZero and Vitabite are foods for special medical purposes and must be used under medical supervision.