Preheat your oven to 350°F (175°C). Place a rack in the center of the oven for even baking of the crust and filling.

In a medium bowl, stir together the graham cracker crumbs, granulated sugar, and fine sea salt. Pour in the melted butter and mix with a fork until the crumbs are evenly moistened and resemble wet sand. If the mixture looks too dry or crumbly, add 1 more tablespoon of melted butter.

Pour the crumb mixture into a 9-inch pie dish. Using your fingers or the bottom of a measuring cup, press the crumbs firmly into the bottom and up the sides of the dish. Pack it tightly for a sturdy crust and cleaner slices. Bake for 8–10 minutes, until lightly golden and fragrant. Let the crust cool for about 10 minutes while you prepare the filling.

In a large bowl, whisk the egg yolks for 1–2 minutes until slightly thickened and creamy. You don’t need to whip them fully—just loosen them to help the filling set with a smooth texture.

Add the sweetened condensed milk to the egg yolks and whisk until fully combined. Stir in the lime zest, then slowly whisk in the lime juice and vanilla extract. The mixture will thicken slightly as the lime juice reacts with the milk.

Pour the lime filling into the warm graham cracker crust. Gently tap the pie dish on the counter a few times to pop any large air bubbles and level the surface. The filling should come almost to the top of the crust.

Bake the pie at 350°F (175°C) for 13–16 minutes, just until the edges look set and the center has a slight jiggle, similar to Jell-O. Do not overbake, or the pie may crack and taste overcooked.

Transfer the baked pie to a wire rack and let it cool to room temperature, about 1 hour. Cover lightly with plastic wrap and refrigerate for at least 3–4 hours, or overnight, until fully chilled and sliceable.

When ready to serve, add the cold heavy whipping cream, powdered sugar, and vanilla extract to a mixing bowl. Beat with a hand mixer or stand mixer on medium-high speed until soft to medium peaks form. Do not overwhip.

Spread or pipe the whipped cream over the chilled pie, leaving some of the lime filling visible if desired. Garnish with extra lime zest or thin lime slices. Slice with a sharp, thin knife, wiping it clean between cuts for neat wedges. Serve cold.