Preheat the oven to 160°C fan. Butter the 12 silicone canelé moulds very generously
Heat the milk with vanilla over a medium heat
In a separate bowl, whisk together the sugar, eggs, and egg yolks until pale and fluffy
Add a quarter of the warm milk to the egg mixture, and fold in the flour
Add the remaining milk and melted butter
Add the rum as the very final step, along with the sea salt
Fill your canelé moulds two-thirds full. Bake the canelés for an hour and a half, before turning the heat up to 230°C for 5 minutes
Allow to cool and remove from moulds