I had lemon curd on toast this morning, made doubly delicious by being the product of my own labour. The inspiration to cook it up, yesterday evening, came from having browsed the pages of our slow cooker book and spotted a recipe. The slow cooker acts as a bain-marie, providing a gentle heat in which to warm and combine the ingredients, which are mixed in a heat-proof bowl inside the water bath.
Despite the gentle heat, it is still possible to go wrong. You start with boiling water and the slow cooker on high to melt the lemon (juice and zest), butter and sugar together. I misread the instructions and also mixed in the egg (1 whole and 1 yolk for 55g butter, 100g caster sugar and juice and zest from two small lemons) and took a while to cotton on that the scum forming on the top was not impurities from the butter but scramblings from the egg!
Setting the dish aside to cool, turning the slow cooker down to low and gradually scraping away the coagulated egg proteins during the rest of the process (and filtering the final product through a wire sieve while putting it into a sterilised jar) allowed me to recover from my mistake. Next time though, I think I will blend the lemon juice and sugar on the hob (allowing me to taste for a perfect combination of sweet and sour) and melt in the butter. I will then add that to the mixing bowl, which will already be sitting in warm water in the slow cooker. I might even go so far as to use my infrared temperature gadget to check that the water is below 62ºC (where egg whites begin to set as white solids).