Found the recipe.

Key Lime Pie

4 egg yolks, lightly beaten
sweetener equal to 1/2 cup sugar
1/3 cup Nellie and Joe's key lime juice (sometimes I use closer to 1/2 cup for a stronger lime taste)
2-1/4 teaspoons grated key lime rind (which I never have, which is the reason I use more of the bottled juice)
1-1/2 cups heavy cream

Nut crust in 8-inch pie pan, can prebake a bit if you like, but it's not necessary

1. In the top of double boiler, combine egg yolks, sweetener, and lime juice. Cook the mixture over moderate heat for about 10 minutes, until it coats the back of a spoon. Remove from heat and stir in grated rind, if you are using it. Chill until the mixture thickens, but do not let it become stiff.

2. Whip the cream to soft peaks and fold it into the lime filling. Spoon into the crust and chill, covered, for 24 hours (or as long as you can wait )

The original recipe calls for whipping another cup of cream and piping it onto the filling in a grid just before serving, but I usually skip this; might do it for company, though.

You could skip the crust altogether and just serve the filling as key lime mousse.

Karla