1. To make the candied orange slices, bring the water with the sugar to the boil, drop in the orange slices in a single layer, turn the heat down to a simmer and cook for about 40 minutes, turning the slices over halfway through. Leave to cool in the syrup (but be careful so it doesn’t all set!), then carefully lift the slices and place on a tray lined with parchment. Reserve the syrup – it’s divine.
2. To make the pastry, mix the flour with the almonds, the icing sugar and the zest, then dice in the butter and rub in or mix everything in a standing mixer with a paddle attachment. Beat the egg yolks with the iced water and pour in. Mix or knead to a soft dough, form a ball, wrap it in cling film and chill for at least half an hour.
3. To make the almond cream, beat the butter in a mixer (or a little blender, seeing as the amounts are small and likely to be dispersed around the sides of a large mixer), add the sugar and beat together until smooth. Mix the flour with the ground almonds and beat into the mix. Add the egg and the orange zest and beat well together. Chill until you’re ready to fill the tartlets.
4. To make the ricotta filling, beat the ricotta with the sugar until smooth and creamy, add the egg, then the egg yolk, beating continuously, and the orange zest.
5. Roll out the pastry not too thin, about 5mm, then cut circles much larger than the tartlet tins (mine were 9cm in diameter). Insert them into the tins pressing down around the edge and cut off any overhanging pastry. Prick the pastry with a fork all over and chill in the fridge for at least 15 minutes.
6. Preheat the oven to 190C/375F/gas 5. Place the chilled pastry cases on a baking sheet and fill them to about ¾ height, don’t overfill.
7. Place an orange slice on top of the filling and bake for about 20 minutes: the pastry edges will brown and the filling shout be just set – difficult to check if the orange slice covers it all, but don’t bake longer than 30 minutes, especially the almond ones.
8. Remove from the oven and place on a wire rack. Unmould them when cold and drizzle some reserved orange syrup* on top before serving.
*if the syrup has set, add a little fresh orange juice to it, heat it up in a microwave and mix in.