I like to bake macarons, but when doing so, I always have leftover egg yolks. Since I really don’t like throwing away food unnecessarily, I tend to make lemon curd with them. I have tried a few different recipes and approaches and found one way that has worked well for me the last few times.
Lemon curd is very versatile and nice to have in the fridge. I use to fill macarons, on desserts, with cakes or even on ice cream. The acidity fits very well with heavy chocolate desserts, like brownies or a chocolate mousse. Or, you can of course use it to make a lemon meringue pie too.
You can easily scale up or down the recipe according to the number of egg yolks you have, but here is the basic recipe I use:
4 egg yolks
175 grams sugar
Zest of 1 washed lemon
75 ml freshly squeezed lemon juice (strained)
50 grams softened butter
Whisk the all the ingredients, except the butter in a heat proof bowl or small pot until it’s well mixed. I normally use a whisk and not a mixer to do this.
Fill a larger saucepan with water, about 1/3 full and bring to a simmer. Place the bowl with the lemon mixture in the simmering water, creating a double boiler. Stir constantly with a whisk until the mixture thickens. This process takes approximately 10 minutes when you have found the right temperature. It must be kept low enough to avoid the eggs curdling.
When it has thickened, remove if from the heat, add the butter to the mixture and stir until it is all incorporated.
Leave to cool a little before transferring to an airtight container. I normally use glass jars. Store in the fridge.
Since I mentioned macarons, lemon curd makes wonderful filling for macarons. Make sure to store the macarons in the fridge, else they will be soaked in sticky lemony mess.
I prefer to use a smaller saucepan when making this as it protects a little better from the heat compared to just a steel bowl.