Sift the flour into a bowl and make a well in the middle. In a jug beat the egg, sugar, milk and water. Pour into the well and gradually incorporate the flour stirring with a knife.
Once the dough has come together, tip onto a floured surface and knead for 5 minutes until it is smooth and soft. Set the dough aside to rest for 10 minutes.
After the 10 minutes, tip the tbsp oil over the dough and knead quickly for 30 seconds to mix in the oil. Shape the dough back into a ball and place in a bowl. Cover with a damp tea towel and leave to rest for 2 hours.
Once rested, shape the dough into 5 equal balls and place onto an oiled baking tray. Cover with cling film and leave for a final 30 minutes.
Heat your grill to high. Lightly oil a work surface and roll a ball of dough out, pretty much as thin as you can, to about 2 mm. Use oil instead of flour to prevent the dough from sticking.
Heat a frying pan as hot as you can on the hob (you need to use a frying pan that can go under the grill). Once hot, place a rolled naan onto the pan and count to 20 seconds. Now place the pan under the grill and wait for the naan to puff up and cook. This will take between 30 seconds and 1 minute. Be careful not to let it burn.
Take the naan out from the grill and place in a folded tea towel to keep warm while you cook the others. Brush with melted butter and serve.