Pour the milk into a medium size saucepan and whisk in the flour

Put the lemon peel and cinnamon quill into the milk and place on the stove on a medium temperature

Whisk frequently until the milk starts to thicken then whisk continuously for 1 minute

Take off the heat and set aside

Pour the water into a small saucepan and add the fructose

Place onto the stove on a low temperature and stir until the fructose dissolves

Increase the temperature and bring to the boil until it reaches 106° Celsius

Slowly pour the sugar syrup into the milk while whisking

Leave to cool slightly then strain into a jug

Place the egg yolks into a lipped jug and lightly whisk

Slowly pour the milk mixture into the eggs while whisking

Once combined cover with cling film and set aside to cool completely

Unroll the puff pastry onto a lightly floured surface

Roll into a tight sausage shape along the width, trim the edges then roll out to 18cm

Cut into 12 equal discs of 1.5cm each and place into the fridge

Lightly spray a muffin tin and take one of the discs out of the fridge

Place the disc swirl side facing up and roll as thin as possible

Place into one of the muffin tin holes with the pastry rising just above the tin

Repeat until all 12 holes have pastry in them then place the muffin tin into the fridge for 20 minutes

Preheat the oven to 220° Celsius

Carefully pour the custard into the pastry cases, to just below the lip of the tin

Bake for 25 minutes then remove from the oven

Leave to cool in the tin for 5 minutes before carefully removing the pasteis de natas

Set aside to cool completely on a wire rack