Recipe is from the Farmhouse Kitchen Book 3 by Yorkshire Television (1982).
75g to 100g butter
225 granulated sugar
1 extra yolk
(Make sure you have jars ready, sterilised at 110C or 225F)
1. Remove the zest of the lemon by grating or peeling the fruit very finely with a potato peeler.
2. Squeeze out the juice and save.
3. Put rind, juice, butter and sugar in a baine-marie. Bring mixture into a simmer, keep stirring until sugar dissolves. (Be careful that no water splashes into the mixture.)
4. In a separate deep bowl, crack the eggs and fork up to remove the germ (ie, those white stringy cords)–do NOT whisk.
5. Pour the prepared fruit mixture over the eggs through a strainer and return to the double boiler.
6. Cook until curd thickens, stirring in ONE direction. (‘Might take 30 to 45 minutes before it is really thick). Stir every 4 or 5 minutes.
7. Pour into the sterilised jars and put a waxed tissue on top. Only put the jam pot covers as it cools. (Curd will also thicken a little more as it cools down.)
8. Keep in the ref. Good for 6 weeks.