1. Slice lemons paper-thin, rind and all. Remove any seeds. place in bowl and add sugar. Mix until slices are well coated. Let stand overnight.
2. Next day, line 20 cm pie plate with half the pastry. Beat eggs well and fold into lemon-sugar mixtures.
3. Pour into curst. Seal with top crust. Cut vents to allow steam to escape.
4. Bake at 230ºC or 15 minutes, then reduce heat to 375 and continue baking for 25-30 minutes, until knife inserted in center comes out clean.
5. Cool before cutting. Serve with whipped cream if desired.