If you don’t have store-bought caramel or dulce de leche on hand, a simple way to make your own is by simmering a sealed can of sweetened condensed milk. Place the unopened can in a large pot of boiling water, ensuring it is completely submerged, and boil for 3 hours. Be sure the can remains fully covered with water the entire time to avoid bursting.

Preheat your oven to 250°F (120°C) and position the oven rack in the center. Line a baking sheet with parchment paper and draw three 6-inch circles as a guide. Flip the parchment over so the drawn circles are on the underside. Finely chop the pecans and toss them with 1 tablespoon of powdered sugar, then set aside.

In the bowl of a stand mixer fitted with the whisk attachment (or using a hand mixer), beat the egg whites and cream of tartar on medium-low speed until soft peaks form. Gradually add the granulated sugar, one tablespoon at a time, and continue beating on high speed until the meringue forms stiff, glossy peaks. Beat in the vanilla extract. Sprinkle the vinegar and cornstarch over the top and gently fold them in using a rubber spatula. Gently fold in the prepared pecans.

Transfer the meringue to a piping bag fitted with a large round tip. Using the circles on the parchment as a guide, begin by piping a dot in the center of each circle. Then, in one continuous spiral motion, work outward to fill the circle. Use an offset spatula to smooth the surface.

Bake the meringue layers for approximately 1 hour and 30 minutes, or until the outside is dry and crisp. Once baked, turn off the oven, leave the door slightly ajar, and let the meringues cool completely in the oven for several hours. The cooled meringue layers can be stored in an airtight container in a cool, dry place—or in the refrigerator—for several days.

In the bowl of a stand mixer or a large mixing bowl, combine the heavy cream, powdered sugar, and vanilla extract. Whisk on high speed until stiff peaks form.

Once the meringue layers are completely cooled, begin assembly by placing the first meringue layer on a serving plate. Spread a layer of caramel over the top, followed by a layer of whipped cream. Repeat the same process with the second layer. For the top layer, place the final meringue on top, spread with whipped cream, and drizzle generously with caramel. Finish with a sprinkle of chopped pecans if desired.