Start by making the roll-in. Mix the margarine and flours well then spread out onto a sheet of cling wrap. Spread out roughly then top with another sheet of cling wrap.
Using a rolling pin, roll the fat out until 1/2cm thick to make 30 x 20cm rectangle. Close the ends of the cling wrap and place in the freezer until hard.
In the meantime, prepare the dough by mixing the yeast and water in a mixing bowl.
Cover and place in a warm place until frothy. Then add the rest of the ingredients in the bowl of a mixer using the dough hook attachment. Add the flour gradually to form a stiff dough (depending on the gluten content of your flour, you may use more or less, so adding it gradually is important.)
Knead for about 4 minutes then allow the dough to rest for 20 minutes.
Roll the dough out on a floured surface to 1cm thick then place the chilled butter roll-in on top. Do a simple 3-fold (like folding a business letter) and roll out again to 1cm thick. Cover and place in the freezer to rest for 20 minutes.
Roll the dough out once again to 1cm thick then do another 3-fold. Rest again in the freezer for 20 minutes before doing the last fold and rest.
Roll the dough out again to 1cm thick and cut out with a round cookie cutter and a smaller one, to create the hole in the centre.
Place the pastry circles onto a lined and floured baking sheet, cover lightly and allow to proof in a warm place until doubled in size.
Preheat the oil to 165C and deep-fry the cronuts in batches until golden and puffed. Drain on paper towel and allow to cool completely.
If you would like to dredge them in sugar, do so while hot.
If you would like to bake them, bake in a preheated oven at 200ºC for 10-15 minutes or until golden and puffed.
To make the pastry cream:
Heat the milk and vanilla until just below boiling point.
Cream yolks, sugar and flour then gradually pour in the hot milk while whisking. Return the mixture to the pot and cook, while stirring until thick.
Place in a bowl, cover the surface with clingwrap and allow to cool completely before folding in the whipped cream.
Place the cream in a piping bag with a small plain nozzle.
To make the glaze:
Whisk the egg white slightly then add enough icing sugar to form a stiff paste. Add the lemon juice and orange blossom water.
To assemble, poke 3 holes in the bottom of each cronut with a chopstick or knife then pipe pastry cream into the bottom of each.
Dip the tops in the glaze and allow to set. Serve immediately. Recipe reprinted with permission of TheKateTin. To see more recipes, click here.