Pre-heat oven to 200°C/Fan 180°C/Gas Mark 6.
To make the shortbread place butter and caster sugar in a bowl and beat until light in colour and texture.
Fold in Fate Low Protein All Purpose Mix and using your hands, mix and squeeze the mixture until it binds together (add water as needed to form a manageable dough).
Transfer to a surface lightly dusted with Fate Low Protein All Purpose Mix and continue to knead the dough for approximately 30 seconds or until smooth.
Roll out to a thickness of ½ a centimetre and place onto a lightly greased 8’’ x 11’’ baking tray.
Place into pre-heated oven for 20-25 minutes, until pale golden in colour. Once removed from oven leave to cool.
To make the caramel sauce add butter and brown sugar into a saucepan over a low heat and stir until butter has melted and sugar has dissolved.
Add ProZero, bring to the boil and simmer for 15 minutes stirring continuously until the mixture has reduced and thickened. Take off the heat and leave to cool for 15 minutes.
Pour the cooled caramel sauce over shortbread and place into the refrigerator for approximately 30 minutes, or until set.
Melt Vitabite slowly in a bowl over a pan of hot water. Pour over the set caramel and return to refrigerator for approximately 30 minutes, or until chocolate has set.
Cut into squares.
Fate Low Protein All Purpose Mix, ProZero and Vitabite are foods for special medical purposes and must be only be used under strict medical supervision.