The combination of flavors and textures in this pie is utterly irresistible: sweet-tart passion-fruit puree is amped up with condensed milk, then poured into a crisp, salty crust and piled high with toasted meringue.
Preheat oven to 350 degrees.
Pulse crackers in a food processor until finely ground. Pulse in butter and granulated sugar until combined. Firmly press into bottom and up sides of a 9-inch pie dish. Bake until golden brown, 18 to 20 minutes. Transfer to a wire rack; let cool completely.
Reduce oven temperature to 325 degrees. In a medium bowl, gently whisk together condensed milk, egg yolks, and passion-fruit puree. Pour filling into crust.
Bake until center is set but still quivers when pie dish is nudged, 15 to 17 minutes. Transfer to a wire rack; let cool completely.
Add topping shortly before serving. In the bowl of a mixer fitted with the whisk attachment, beat egg whites on medium-high speed until frothy. Increase speed to high and gradually add both sugars and salt, beating until stiff peaks form, 5 to 7 minutes. Pipe or spread meringue on pie, making sure it touches the crust all around. Lightly brown meringue with a kitchen torch.