Make the crepes to begin with. In a large bowl whisk together the eggs, sugar and vanilla. Sieve in the plain flour and mix with a little of the milk to make a thick batter. Gradually add the milk until the batter is smooth and a similar consistency to single cream. Finally whisk in the melted butter then transfer to a jug, cover and leave in the fridge to rest for 30 minutes, preferably longer.
Heat a little oil in the square pan and pour in approx 125ml of the batter, tilting the pan to get into the corners. Cook for a couple of minutes before flipping and cooking for a further 30 seconds on the other side. Repeat the process so you have 5 pancakes.
Make the filling by beating together the butter, icing sugar and vanilla for a few minutes until light and fluffy. Add the mango puree and beat again.
Peel the mango and cut the two cheeks off- slice one cheek thinly, and cut the other into 4 thick slices, cutting lengthways.
On a long sheet of greaseproof paper lay out 2 of the crepes, so they slightly overlap at the end and the short end is nearest to you. Spread the surface evenly with some of the mixture, then lay two of the mango pieces at the end nearest you, ready for rolling. Roll up tightly, and once you get a couple of inches from the end, lay another crepe directly on top of the end of the last one, and one on the end of the third- just like before. Spread the crepes with more filling and before you get rolling, lay the final two pieces of mango down at the end of the second crepe. Keep rolling and spreading until you’ve used all 5 crepes up, rolling as tightly as possible all the way. Once you get to the end, place on a serving plate, seam side down.
Cut the ends off to neaten it up. Decorate with the slices of mango over the top and dust with icing sugar before slicing up and serving.