heat oven to 180 . beat butter/marg till soft
add eggs, sugar, flour, milk and zest and mix till it comes together
divide between 2 sandwich tins and cook for 25-30 mins
meanwhile make the custard by adding half a pint of boiling water and mixing (thicker custard less water) then add lemon curd and mix well
leave to cool along side cakes when they out if oven
when cool as as much custard you want to one of the cakes then place other on top.
for the glaze I just mixed icing sugar and lemon juice to a thick pouring consistency and drizzled on top.