Bake pie crust according to package instructions. Cool to room temperature on rack.
Mix brown sugar and cornstarch together in a small saucepan. Whisk together egg yolks and heavy cream and add to brown sugar mixture. Cook over medium heat, whisking constantly until thickened – approximately 10 minutes.
Remove from heat and stir in butter, vanilla extract, and pecans. Pour into baked pie crust. Refrigerate for at least 4 hours or until pie filling is set. Top with whipped cream and serve.