Gently heat the milk and lemongrass; bring it up to a boil for 5 seconds and immediately take the pan off the heat.
Crack your eggs into a mixing bowl and mix in the sugar, vanilla extract and coconut milk. Remove the lemongrass from the milk, and whisk it through the egg mix. Strain the mixture into a jug/bowl with a pourer and set aside. Heat a full kettle.
Check your caramel has set in your ramekins. Gently press a finger onto the top of the caramel;you want a bit of resistance. If you’re ready, pour the custard onto the caramel slowly over the back of a large spoon, making sure the custard is not flowing beneath the caramel – in which case wait another 5 minutes. Evenly fill each ramekin and place them into the baking tray.
Taking care not to pour the water onto the desserts, pour the hot water from the kettle and fill the baking tray to half-way up the ramekins. Cover the tray tightly with foil and place into the oven to cook for 25 minutes.
Remove the foil and continue to bake for approximately 10 more minutes until your custard has set.You can test this by carefully touching the surface of the custard – if it is still fluid, it needs to cook a little longer.
Once the custards are set, remove them carefully from the water bath. Allow the ramekins to cool to room temperature and place in the fridge until you’re ready to serve!