In a clean, dry bowl, whisk the egg white on high speed until soft peaks form.
Gradually add the sugar, 1-2 tablespoons at a time, whisking until each addition is fully dissolved before adding more. Be patient and take your time to ensure the sugar dissolves completely.
Once all the sugar is incorporated, continue whisking for 10-15 minutes, or until the mixture is thick, glossy, and holds stiff peaks.
Add the cornflour and vinegar and whisk until just combined.
Preheat oven to 150°C (300°F).
Draw a 20cm circle on a sheet of non-stick baking paper using a pencil. Place the paper, pencil-side down, on a baking tray.
Spoon the meringue mixture into the circle, shaping it into a neat round.
Reduce oven temperature to 120°C (250°F) and bake for 1 hour.
Turn off the oven and let the meringue cool completely inside the oven.
To prepare the peaches, heat a pan over medium heat. Add the peach slices with a drizzle of honey and a sprinkle of thyme leaves.
Cook until the peaches are tender and caramelised.
When ready to serve, whip the cream on medium speed until soft peaks form. Add the honey and whip until combined.
Construct the pavlova by adding cream between the two layers and a generous layer of cream on top. Top with the grilled peaches and sauce from the pan and an extra drizzle of honey.