Lime curd is smooth and has a rich lime flavor. You can add more coloring to make is easier to distinguish from lemon curd, if you like.
This is an old recipe that was in one of my grandma's files. I have updated it to use the microwave oven instead of a double boiler (since I don't even have one anymore).
Whisk well until mixture is smooth.
Next, stir in lime zest, juice, and food coloring, if using (use a very small amount).
Repeat directions between the ** until the curd is thick enough to coat the back of a metal spoon and reaches a temperature of 196 degrees on a candy thermometer.
For larger batches, store the finished lime curd in sealed canning jars.
Boil canning jars and lids in a water bath for five minutes. Then pour the hot curd mixture into the jars, use a peper towel to clean edges of jars of any curd, top with a lid, and screw on a cap. Turn the jars upside down and let them sit that way for five minutes so the air at the top can travel to the bottom of the jar.
When you invert the jars, they will seal themselves. This will keep the curd fresh for several months at cool room temperature.