Preheat the oven to 120°C, fan 100°C, gas mark ½. Line two baking trays with baking paper (you can fix this in place with a tiny blob of the meringue mixture before baking).
Separate the whites from the yolks of 6 medium eggs into a large spotlessly clean bowl (any grease in the bowl will stop the egg whites from foaming fully).
Using an electric hand-held whisk, beat the egg whites until they form stiff peaks (when you lift the beaters out of the mixture it should stand up in peaks).
Slowly add the caster sugar – 1 tablespoon at a time – and continue whisking until it is well combined and you have a meringue mixture that’s thick and glossy.
Using a large metal spoon, drop 6 generous dollops of the mixture onto the prepared baking sheets, using up all the mixture, and swirl lightly to make dome-shapes.
Bake for 2 hours, then turn the oven off and leave in the oven for a further hour to cool. Keep in an airtight container for up to 3 weeks.
Customise your meringues with these different flavour ideas:
Pistachio - stir chopped pistachios and some green food colouring through the mixture.
Rose - for a gentle rosy hue, stir through a little red food colouring and add a few drops of rose water for flavour.
Chocolate - gently fold cocoa powder or grated chocolate through the mixture. For a dramatic effect, keep the chocolate in swirls.
Lemon - go for a citrus twist by adding some finely grated lemon zest and a few drops of yellow food colouring.