Heat the oven to 350 °F and grease an 8x8-inch baking dish. Coat the corners and sides well so the fragile baked meringue releases more easily.

Put the Ritz crackers in a large ziplock bag and crush them into small pieces. A mix of fine crumbs and small fragments gives the finished layer more texture than cracker dust alone.

Spread the crushed crackers over a large baking sheet and bake for 5 minutes, then stir and bake for 5 minutes more. Let the crumbs cool after they smell buttery and lightly toasted.

Beat the egg whites in a large bowl or stand mixer for 1 minute until pale and foamy. The whites should look bubbly and light before the sugar is added.

With the mixer running, add the granulated sugar gradually and beat for 3 to 5 minutes more. Stop when the meringue is thick, shiny, and marshmallow-like rather than dry or grainy.

Fold the pecans, cooled cracker crumbs, baking powder, vanilla extract, and salt into the meringue just until no dry pockets remain. Work gently and stop as soon as the mixture looks evenly combined to avoid knocking out the whipped air.

Scrape the mixture into the greased baking dish and spread it evenly to the edges. The surface will look airy and slightly uneven, which is exactly what you want.

Bake for 30 minutes. The edges should be set and just beginning to turn pale golden, with a sweet, nutty cracker aroma.

Let the baked torte layer cool for 1 to 2 hours before adding the topping. The dish should no longer feel warm when you hold your hand near the center.

Beat the chilled heavy whipping cream with the powdered sugar and vanilla extract until stiff peaks form, then spread it evenly over the cooled torte. The cream should hold a peak that stands upright when the beaters are lifted.

Chill the assembled torte for at least 1 hour, then garnish with chocolate shavings if desired. The topping should feel set and the baked layer should cut more cleanly after chilling.