Heat the oven: Preheat to 350°F (175°C). Set a rack in the center.

Make the crust: Stir graham crumbs, sugar, and salt in a bowl. Add melted butter and mix until the crumbs look like damp sand. Press the mixture firmly into a 9-inch pie dish, going up the sides. Use the bottom of a measuring cup to pack it tight.

Par-bake the crust: Bake for 8–10 minutes, until fragrant and lightly set. Let it cool while you make the filling. Keep the oven on.

Whisk the filling: In a medium bowl, whisk egg yolks until slightly thickened, 30–45 seconds. Add condensed milk, lemon zest, vanilla, and salt. Whisk in the lemon juice last, mixing until smooth and creamy. The mixture will thicken as the lemon juice reacts with the milk.

Fill and bake: Pour the filling into the warm crust. Smooth the top. Bake for 12–15 minutes, until the edges look set and the center still has a slight wobble. Do not overbake.

Cool and chill: Let the pie cool to room temperature, about 1 hour. Then cover and chill for at least 3 hours, preferably 6 hours or overnight, until fully set.

Make the whipped cream: Beat cold cream, powdered sugar, and vanilla to soft peaks. Spread or pipe over the chilled pie.

Garnish and serve: Add a sprinkle of lemon zest or a few thin slices. Slice with a warm, dry knife for clean cuts.