1) In large mixing bowl, add gelatin and puree and stir. Let gelatin sit and swell or 'bloom'. Greaseproof paper the brownie pan.
2) In a large saucepan, add caster sugar, golden syrup and water and stir to combine. Brush the sides down with water to remove any sugar crystals stuck to the sides. Bring to a boil, add a sugar thermometer and cook to 120 degrees C.
3) Whisking furiously with a hand mixer (or in a stand mixer), slowly add hot sugar to the gelatin mixture. Whisk thoroughly until thick bubble gum like strands form. Add Vanilla.
4) Spray everything with pan spray, spatulas, brownie pan, spoons, hands, etc.
5) Scoop marshmallow mix into brownie pan and spread evenly. Sift cornflour on top and let rest for 2 hours.
6) When rested, using a greased knife, cut into cubes and toss in cornflour. Sift from cornflour and bag.
Recipe from Bea's of Bloomsbury