Whisk lemon juice, sugar, and eggs together in a medium size bowl, off heat. The bowl should be big enough to rest on top of a medium sized pot with the bottom inch or 2 resting below the pot rim.
1/2 cup lemon juice, 1 cup sugar, 2 tbsp lemon zest, 4 egg yolks, 1 whole egg, pinch sea salt
Create a double boiler by filling a pot with about an inch of water, bringing it to a gentle boil, and placing the bowl with the whisked ingredients over top of the pot.
Cook the egg, lemon, and sugar mixture gently over medium-low heat for about 10 minutes, whisking constantly, until the mixture coats the back of a spoon. Note: If it doesn’t coat a spoon after 10 minutes, keep cooking and whisking for a few more minutes until it thickens slightly.
Remove the bowl from the heat and whisk in the butter, one tablespoon at a time, for about a minute until it's fully emulsified (if it's not emulsified, it may cause the curd to be grainy). You can also use an immersion blender to mix it in for an even smoother texture.
8 tbsp butter
For extra smoothness, strain the lemon curd through a fine mesh strainer.
Place the finished curd in a jar or container and cover with a lid. Chill in the fridge until it’s cold and set, about 3 hours or up to overnight. This recipe makes between 1 and 1 1/2 cups of curd.
Enjoy with yogurt, toast, or even as a topping for vanilla ice cream.