Make the ice cream (if using). Heat 750ml of the milk in a heavy-based saucepan over a medium heat, stirring constantly. Add the sugar and simmer until reduced to 500 ml. Turn the heat down to low, add the condensed milk and glucose and stir. Soak the gelatine in cold water until soft. Stir it into the warm milk, then add the remaining milk. Leave to cool. Transfer to an ice-cream machine and churn for 15–20 minutes, until thickened. Transfer to a freeze-proof container and place in the freezer.
Make the pastry by lightly rubbing the butter into the flour, then mix in the egg. Using your hands, combine to form a smooth dough, adding a tablespoon of water if it’s too dry. Shape into a ball, flatten to form a disc, cover with cling film and set aside to rest in the refrigerator for 20 minutes.
Preheat the oven to 160ºC/ Fan 140ºC/Gas 3 and grease a 23 cm flan ring. Roll out the dough on a lightly floured surface to about 5 mm thick and line the flan ring. Cover with baking parchment and baking beans, then bake blind for 20 minutes. Remove the paper and beans and leave to cool in the flan ring. Reduce the oven temperature to 150ºC/ Fan 130ºC /Gas 2.
Heat a heavy-based saucepan over a low heat and melt together the syrup, jaggery, lemon juice and eggs. Once everything is incorporated, add the cream. Remove from the heat, then fold in the breadcrumbs. Spoon the mixture into the pastry case and return to the oven for 45 minutes until set and golden. Remove from the oven and allow to cool.
Sprinkle with a little salt and serve with the ice cream.