Pre-heat oven to 200°C/Fan 180°C/Gas Mark 6.
Place butter, hard margarine and caster sugar into a mixing bowl and beat until light in colour and texture.
Fold in Fate Low Protein All Purpose Mix.
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 the dough 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.
Remove from oven and cool on a wire rack.
Add Vitabite chunks and butter to a heatproof bowl. Melt by placing bowl over simmering boiling water, stirring occasionally or melt in the microwave on a low heat.
Fold the shortbread chunks and Freedom White Mallows into mixture (be careful not to break up shortbread too much).
Line an 8” x 11” baking tray with parchment or greaseproof paper and pour in the mixture.
Level out using a spatula and place into the refrigerator for approximately 30 minutes, or until set.
Once set, remove from baking tray and cut into bite sized chunks.
Fate Low Protein All Purpose Mix and Vitabite are foods for special medical purposes and must only be used under strict medical supervision.