Wash the orange, rub dry well and rub the peel. Squeeze the orange. Wash, clean and slice the strawberries. Mix with orange juice and 25 g sugar, put aside.
Separate eggs. Beat the egg whites until stiff, pour in 25 g sugar. Beat the egg yolks, salt, 50 g sugar and orange zest until thick and creamy with the whisk of the hand mixer. Sift the flour over it and fold in.
Egg whites in two portions and fold into the egg yolk mixture. Arrange the strawberries in an ovenproof dish. Place the mixture on top and spread loosely. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 25-35 minutes.
Dust with icing sugar and decorate with orange zests.