Actually, it's a lime-lemon curd and it packs a real punch, reminding me of the sour sweets I used to enjoy when I was a child. I used "Nellie and Joes Key West Lime Juice," which I purchased from Citarella, and regular lemon zest. So far I have not seen key lime fruits in New York. Just being able to pour the juice instead of laborsome lime squeezing is a benefit in itself.
The recipe is very easy, the only time consuming element being the 20-25 minute stirring at the stove once all the ingredients are added.
1 cup sugar
1/4 cup butter, cut into ounces
3/4 cup Nellie and Joes Key West Lime Juice
1 TBS. lemon zest (regular lime zest is too bitter for my taste)
2 eggs, beaten
1. Place the sugar, butter, lime juice, lemon zest in the top of a double boiler, stir over medium-high heat until butter melts. Mix 2 tablespoons hot lime mixture into the eggs and stir to blend.
2. Reduce heat to medium until water simmers. Slowly whisk egg mixture into the lime mixture. Cook over the double boiler until lime mixture thickens and coats the back of a wooden spoon, 20 t0 25 minutes. Cool slightly, then spoon lime curd into a clean, glass jar (or place Saran Wrap right against the curd in a bowl.) It seems that key lime juice is quite yellow.
Bench Notes: Tried recipe again, this time with 1/2 cup lime juice plus 1/4 cup water added, only 1 tsp lemon zest and an additional 2 Tbs. sugar. This went over better with people who,unlike me, do not like mouth-puckering sour.