Preheat the oven to 250°F (120°C). Line 2 baking trays with baking paper, sticking it firmly on the tray with a little meringue.

Put the egg whites in a clean bowl of a free-standing electric mixer fitted with a whisk attachment and beat until the whites double in volume and hold a slightly bent peak when you lift the whisk. Add half the sugar, a tablespoon at a time, incorporating each tablespoon completely before adding the next one. Tip in the remaining sugar and whisk until the whites are stiff and glossy. Fold in the ground mastic and vanilla extract with a metal spoon.

Reduce the oven temperature to 225°F (110°C).

With two large metal spoons, take a big spoonful of the meringue mixture, the size of a small orange and scrape it off placing it onto the baking trays. Repeat spacing the meringues well apart. I like large individual spiky ones. Top with chopped pistachios, flaked almonds or sprinkle with cocoa powder when making for afternoon tea or leave plain if using as a dessert.

Bake for about 70 minutes or until they are crisp, depending on the size of the meringues.

Check that the underside is firm to the touch and dry. Turn off the oven and allow the meringues to cool completely in the oven for 30 minutes or overnight as I do.