Ultra-creamy, tart-sweet lemon filling in a toasty almond-graham cracker crust, delivering bright citrus flavor and a silky, custardy bite—like lemon bars in a cool, refreshing pie.
Preheat the oven to 350°F (177°C).
Make the crust: In a food processor, pulse the graham crackers and almonds into fine crumbs (a few larger nut pieces are OK). Transfer to a medium bowl and stir in the sugar.
Add the melted butter and stir until the mixture is evenly moistened and sandy; break up any large clumps.
Press the mixture firmly and evenly into an ungreased 9-inch pie dish, going up the sides. Use medium pressure—do not pack too hard. Optionally use a flat measuring cup to smooth the bottom and a spoon to round the inside edge.
Pre-bake the crust for 8 minutes. Leave the oven on.
Make the filling: Whisk together the sweetened condensed milk, lemon juice, and egg yolks until completely combined and smooth.
Pour the filling into the warm crust.
Bake for 19–21 minutes, until the center is only slightly jiggly and the pie is mostly set.
Cool completely on a wire rack. Then cover and refrigerate for at least 1 hour (up to 3 days). After about 8 hours, lightly cover the surface.
Garnish with whipped cream, lemon zest, lemon slices, and/or almonds, or top with meringue if desired. Slice and serve, wiping the knife clean between cuts.
Store leftovers covered in the refrigerator for up to 1 week.