Too often lemon tarts are too sweet. Tesco used to produce one in their Finest range that was excellent.
This one has a good tange, but you can add or subtract sugar to taste.
1 Large egg yolk
1 Tbsp water
4 Lemons - juice and zest
Pastry - flour, butter sugar - whizz to breadcrumbs. Add yolk and water - whizz.
Chill in fridge. Line tin and blind bake for 12 mins @ 200°C
Reduce temp to 160°C Leave pastry to cool.
Whizz eggs, cream, sugar, lemon juice and zest. Sieve. Pour into base.
Bake for 30/35 mins or 'til set. Sprinkle with icing sugar just before serving.