Citrus curds are one of my favorite winter treats when lemons, oranges and limes are so abundant. A curd is yummy on toast or cake. I like to drop a dollop into a baked puff pastry shell and top with fresh whipped cream. This lime curd is especially good spread over a graham cracker.
When making curd the key is to cook it slow and never stop whisking. If it cooks too fast you will end up with bits of cooked egg. The easiest way to prevent this is to use a double boiler. If you don't have a double boiler a heat-safe bowl placed over a pot of boiling water will work.
In the top pan of your double boiler whisk together the lime juice, sugar, salt and eggs. Set the top pan over the simmering water in the bottom pan and continue to whisk the mixture until it becomes thick. This should take about 10 minutes. If you find that the curd is reluctant to thicken, it could be that the water temperature in the double boiler is too low.
Remove the top portion of the double boiler, add the butter a small piece at a time and whisk until the butter is melted.
Stir in the zest and transfer to a bowl.
Place plastic wrap on top of the curd to prevent a skin from forming and chill in the refrigerator for at least an hour.
This will keep in the refrigerator for about 1 week.
Time to prepare: 1 hour, 20 minutes.