With the rack in the middle position, preheat the oven to 180 °C (350 °F). Line a 20-cm (8-inch) springform pan with parchment paper.
In a bowl, combine the flour, cocoa powder, and baking powder. Set aside.
In another bowl, beat the egg and brown sugar with an electric mixer until the mixture doubles in volume, about 5 minutes. On low speed, add the dry ingredients alternately with the oil and milk.
Pour the batter into the prepared pan. Bake for about 20 minutes or until a toothpick inserted in the centre of the cake comes out clean. Cool on a wire rack in the pan. Freeze for 15 minutes.
Spread the ice cream on the cake. Set aside in the freezer.
In a bowl, whip the cream and half the sugar with an electric mixer until stiff peaks form. Set aside.
In another bowl, beat the egg whites with an electric mixer until light and foamy. Gradually add the remaining sugar, beating until stiff peaks form. Add the strawberry purée and fold it in with a spatula. Fold in the whipped cream the same way. Spread in the pan on the ice cream and freeze for 4 hours or overnight.
To get 250 ml (1 cup) of strawberry puree, puree 500 ml (2 cups) of fresh or frozen and thawed strawberries in a food processor.
Recipes with the "Healthy Pick" stamp have been evaluated by a registered dietitian member of the Ordre professionnel des diététistes du Québec.