Preparation

Make the shell

• Position a rack in the lower third of the oven and heat the oven to 275°F. Line a baking sheet with parchment. Draw an 8-inch circle in the center of the parchment, and then turn the paper over (you’ll still see the circle).
• Mix 2 tsp. of the sugar with the cornstarch and set it aside.
• In a stand mixer fitted with the whisk attachment (or in a large bowl using a handheld electric mixer), beat the egg whites on medium-high speed until soft peaks form, about 2 minutes.
• With the mixer running, slowly add the remaining 1-1/4 cups sugar, about 1 Tbs. at a time, taking 2 to 3 minutes to add it. Sprinkle in the cornstarch-sugar mixture, then add the lemon juice, vanilla, and salt. Continue beating until glossy stiff peaks form, another 1 to 2 minutes.
• Pile the meringue onto the parchment circle and use an offset spatula or the back of a spoon to spread it into an 8-inch round, about 2-1/2 inches high around the edge with a slightly concave center.
• Put the meringue in the oven and turn the heat down to 250°F. Bake until crisp, dry, and slightly colored on the outside, about 45 minutes. (The meringue will spread a little during baking.) Rotate the baking sheet and continue baking until hard on the outside and slightly darker, about 45 minutes more. Turn off the heat and leave the meringue in the oven to dry for at least 30 minutes. Cool completely and gently peel off the parchment. Don’t worry if there are cracks or the center caves in slightly.

Make the filling

• Combine the berries with 2 Tbs. of the sugar and the orange liqueur in a medium bowl. Let stand at room temperature, stirring occasionally, until the berries release their juice, about 45 minutes.
• In a large bowl, beat the cream, the remaining 1 Tbs. sugar, and the vanilla with an electric mixer, increasing the speed from medium high to high as you beat, until soft peaks form, 2 to 3 minutes. Fold in the yogurt.
• Carefully transfer the shell to a serving plate. Just before serving, fill the center with the cream and top with the berries. Use a serrated knife to slice the pavlova into wedges and serve.

Make Ahead Tips

You can make the shell 1 day ahead and leave it in the closed, cooling oven. Or store it, once completely cooled, for up to 3 days in an airtight container.

The whipped cream filling can be made up to 1 hour ahead and refrigerated.