- 1 cup all-purpose flour
- 1 1/2 tsp baking powder
- 5 eggs, separated
- 1 cup granulated sugar, divided
- 1/3 cup 2% milk
- 1/2 tsp vanilla
- 1/2 400-mL can coconut milk
- 1/2 300-mL can sweetened condensed milk
- 1 tsp vanilla
- 1 tbsp rum (optional)
- PREHEAT oven to 350F. Spray a metal 8 x 8-in. cake pan with oil. Line bottom with parchment.
- STIR ﬂour with baking powder in a medium bowl.
- BEAT egg whites in a large bowl, using an electric mixer on high, until foamy. Gradually add 1/4 cup sugar and continue beating until whites are glossy and stiff peaks form when beaters are lifted, 2 to 3 min. Using same beaters (no need to wash), beat yolks with remaining 3/4 cup sugar in a large bowl until pale yellow, 1 to 2 min. Reduce mixer speed to low. Gradually beat in ﬂour mixture, then milk and 1/2 tsp vanilla, until smooth.
- STIR a third of egg whites into yolk mixture, using a rubber spatula, then carefully fold in remaining egg whites until no streaks remain. Pour into prepared pan.
- BAKE in centre of oven until springy and a skewer inserted into the centre of cake comes out clean, 30 to 35 min. Cool completely on a rack, about 1 hour.
- WHISK coconut milk with condensed milk, 1 tsp vanilla and rum in a small bowl until combined. Poke top of cake all over with a skewer. Pour half of coconut syrup over cake and let stand 5 min. Run a knife around edges of cake and invert onto a rimmed serving platter. Remove parchment. Poke bottom of cake all over with skewer. Pour remaining syrup all over cake, spooning any excess drippings back onto the cake until it is absorbed, about 5 min.
- Refrigerate until fully chilled before serving, 1 to 2 hours.