Best Key Lime Pie

Preheat the oven to 350 degrees F

Add the vanilla wafers to a food processor and process them into fine crumbs (or use a rolling pin). Add the coconut, sugar, and butter and pulse or stir to combine

Press the crumbs evenly up the sides and onto the bottom of an ungreased 9-inch pie pan or quiche pan. If using a quiche pan (pictured), only press 1 1/2 – 1 3/4 inches up the sides (because it's deeper than a pie pan)

Bake the crust at 350 degrees F for 8-10 minutes, until lightly golden. Cool completely on a wire rack before adding the filling (about 1 hour)

Whisk the egg yolks together in a small nonreactive saucepan (stainless or enamel). Add the Key lime juice, zest, sugar, cornstarch, and salt and whisk until the cornstarch dissolves. Whisk in the half and half then add the cubed butter

Turn the heat to medium (medium-low if your stove runs hot) and cook, stirring CONSTANTLY, making sure to scrape the bottom and sides of the pan. Cook until the filling thickens to the consistency of pudding and registers about 195-200°F on an instant-read thermometer. (Don’t stop whisking, even while taking the temperature.)

Once thickened, immediately remove the filling from the heat and transfer to a large bowl. Let cool to room temperature, then fold in the sour cream. Taste and add additional lime zest for tangier or powdered sugar for sweeter if desired

Pour the filling into the cooled, baked pie shell. Cover with plastic wrap pressed against the surface of the filling (don't worry about "ruining" the aesthetics of the top, you can make it pretty after chilling). Chill in the refrigerator for at least 4 hours, up to 2 days

You may add the stabilized whipped cream at any point while the pie is chilling and return to the fridge (tented with foil) or skip the gelatin/water and add the whipped cream just before serving

Add the unflavored gelatin to a small microwave-safe bowl, then whisk in the cold water with a fork. Let stand for 5 minutes, then microwave for 20 seconds. Stir the mixture, then set aside while you immediately begin to beat the heavy cream

Add the heavy cream, powdered sugar, and vanilla extract to a large mixing bowl. Whip using an electric hand mixer just until soft peaks form (the peaks flop over when the beaters are lifted.)

Turn the mixer to low and slowly pour in the gelatin mixture. Mix until combined, then increase the speed to medium and continue mixing until stiff peaks form (peaks stand straight up when the beaters are lifted)

Transfer the whipped cream to a piping bag and decorate as desired (serve extra on the side) OR spread evenly over the entire pie. The beauty of stabilized whipped cream is it will hold its shape indefinitely and never weep. If using regular whipped cream, top just before serving

Add the lime slices just before serving (if using) so they don't weep

Run a knife under hot water, or fill a large glass with hot water, and dip the knife in the hot water before each cut. Wipe the knife clean with a towel after each cut, then repeat