Heat oven to 120C/100C fan/gas 1 and line a large baking tray with parchment paper. Whisk the egg whites in a clean bowl using an electric whisk or tabletop mixer until they reach stiff peaks, then add the sugar in 3 lots, re-whisking to stiff peaks every time. Spoon dollops of the mixture onto the baking parchment, cook on the bottom shelf of the oven for 1hr – 1hr15 mins until the meringues are completely hard and come off the paper easily. Leave to cool.
Blitz 1/3 of the strawberries to make a strawberry sauce. In a large bowl whisk the cream with the icing sugar until it just holds its shape. Roughly crush ¾ of the meringues and tip them in with the chopped strawberries and stir, then swirl through the strawberry sauce. Dollop into bowls then crush the remaining meringues, sprinkling the pieces over the top.