Could this be it ??
Lime Sour Cream Pie
Pyewacket Restaurant - Chapel Hill, NC
Gourmet December 1990
For the crust:
1 1/2 cups graham cracker crumbs (about 11 crackers)
1/2 stick (1/4 cup) unsalted butter, melted
For the filling:
1 1/2 tablespoons freshly grated lime zest
1/2 cup fresh lime juice
1 cup half-and-half
3/4 cup sugar
2 tablespoons unsalted butter, softened
5 tablespoons cornstarch
3/4 cup sour cream
Sweetened whipped cream for garnish
Lime slices for garnish
Make the crust: In a bowl stir together the graham cracker crumbs and the butter and press the mixture onto the bottom and up the side of an 8-inch pie plate (1-quart capacity). Bake the crust in the middle of a preheated 350ºF. oven for 8 to 10 minutes, or until it is just crisp, and let it cool.
Make the filling: In a metal bowl set over a saucepan of barely simmering water whisk together the zest, lime juice, half-and-half, sugar, butter, and cornstarch, and cook the mixture, whisking, for 5 to 7 minutes, or until it is thickened and opaque. Let the mixture cool completely. Fold in the sour cream, pour the filling into the crust and chill the pie, covered, for 1 hour, or until it is cold. Garnish the pie with the whipped cream and the lime slices.