Beat butter and icing sugar until pale and creamy. Fold in egg and combined sifted flour and almond meal until soft dough forms.
Turn out onto a lightly flour surface and shape into a disk. Wrap in cling film and refrigerate 30 minutes.
Process mango, sugar and lemon juice in a food processor, scraping down the side occasionally, until smooth. Add eggs and yolks, whiz for 15 seconds.
Strain curd mixture through a course sieve into a medium saucepan, pressing on solids with the back of a spoon to extract all liquid. Cook on low heat, stirring constantly for about 6 minutes until the mixture coats the back of a spoon (don’t overheat).
Remove from heat, whisk in butter. Transfer to bowl, cover surface with cling film and store in fridge 3 hours, til firm.
Roll out pastry onto lightly floured surface until 3 mm thick. Using rolling pin, transfer to a greased 22 cm loose bottom fluted pan. Trim pastry. Refrigerate 1 hour.
Preheat oven to 220°C (425°F) or 200°C (390°F) fan-forced. Line pastry with baking paper and beans or pasty weights. Bake 10 mins. Reduce oven temp to 180°C (350°F) or 160°C (320°F) fan-forced. Cook a further 12 mins.
Spread curd into the cooled tart shell, refrigerate and top with slices of mango just before serving.