Heat the oven to 130°C.
Use an approx 24cm cake tin as a template to draw a circle on a piece of baking paper. Lightly oil the paper, and place in a baking tray
In a large clean bowl, whisk the egg whites with an electric mixer until thick, glossy and holding medium peaks. On a low speed, whisk in 300g of the sugar - a little at a time - and continue to whisk, adding half of the spices and cornflour, until thick and glossy
Spoon the meringue into the centre of the circle on the baking tray, and spread it out to the edges of the circle with a butter knife. You can swirl and shape the meringue at this point
Place in the oven and bake for 15 minutes. Lower the oven temperature to 100°C and cook for a further 45-60 minutes. Turn the oven off and allow the pavlova to cool for a couple of hours or overnight: this minimises cracking
Put the cream and orange zest in a clean mixing bowl and whisk until it forms soft peaks
Spread the curd on the centre of the pavlova. Top with the cream
Just before serving, peel and slice the orange and place the slices on top, sprinkle with flaked almonds and dust with the remaining half of the spice blend