Prep your tools. Heat the oven to 250°F (120°C). Line two baking sheets with parchment. Draw 8–10 circles (about 3 inches/7.5 cm) on the underside as a guide if you like. Make sure your mixing bowl and whisk are spotless and grease-free.

Separate the eggs. Crack eggs one at a time, dropping whites into a clean bowl and yolks into another. Avoid even a speck of yolk. Let whites sit 20 minutes to take the chill off if needed.

Start whipping. Beat egg whites on medium speed until foamy and soft peaks start to form. Add the lemon juice or vinegar and keep beating.

Add sugar slowly. With the mixer running, add the granulated sugar one tablespoon at a time. This should take 5–7 minutes. Beat until the meringue is glossy and forms stiff peaks that hold their shape.

Stabilize and flavor. Sift in cornstarch and add 1/2 teaspoon vanilla. Gently fold with a spatula until just combined—don’t deflate the mixture.

Shape the nests. Spoon meringue onto the lined sheets in mounds. Use the back of a spoon to swirl and create a shallow well in each. Aim for 2 inches tall with neat edges.

Bake low and slow. Place in the oven and bake for 60–75 minutes, rotating pans halfway. The shells should feel dry to the touch and lift easily from the parchment.

Cool in the oven. Turn off the oven and crack the door. Let the pavlovas cool inside for at least 45 minutes, ideally 1–2 hours. This prevents cracking and weeping.

Whip the cream. Beat cold heavy cream with powdered sugar and the remaining 1/2 teaspoon vanilla until soft peaks form. Keep it light and silky, not stiff.

Prep the berries. Hull and slice strawberries if using. Toss mixed berries with a tiny pinch of sugar and a touch of lemon zest if you want extra brightness.

Assemble before serving. Spoon whipped cream into each meringue well. Top generously with berries. Add mint leaves if you like. Serve right away for the best texture.