Prepare the Cake:
Preheat the Oven: Preheat the oven to 325°F (160°C). Line the bottom of an 8” round cake pan with parchment paper. If using a springform pan, wrap the outside with foil to prevent water from seeping in.
Prepare Water Bath: Boil water for a water bath. You’ll need enough to cover 1 inch (2.5 cm) of the pan’s height.
Melt Butter and Milk: Combine milk and butter in a heatproof bowl and microwave until melted. Stir to combine.
Mix with Flour: Sift cake flour into the melted butter and milk mixture. Gently mix with a spatula until smooth. Add egg yolks and mix until combined.
Beat Egg Whites: In a clean bowl, beat egg whites with a mixer until frothy. Gradually add sugar and continue beating until glossy with medium peaks.
Combine Mixtures: Fold a quarter of the beaten egg whites into the yolk mixture. Then gently fold the yolk mixture back into the remaining egg whites until just combined.
Bake the Cake: Pour the batter into the prepared pan. Drop the pan gently on the table to release air bubbles. Place the pan in the water bath and bake for 1 hour 30 minutes, or until a skewer comes out clean. Let the cake cool completely on a rack before cutting and decorating.
Prepare the Macerated Strawberries:
Slice Strawberries: While the cake cools, slice 8 oz (225 g) of strawberries and toss them with 1 1/2 teaspoons sugar. Let sit for 1-2 hours until glossy and sweet. Reserve the liquid.
Make Cake Syrup: Dissolve 2 tablespoons of sugar in 3 tablespoons of hot water. Optionally, add the reserved strawberry liquid for extra flavor.
Prepare the Whipped Cream:
Stabilized Cream (Optional): If using, bloom the gelatin in cold water, then melt it. Whip the cream with confectioners sugar until soft peaks form. Mix some cream with the gelatin, then fold into the rest of the cream and whip to medium peaks.
Regular Cream: Whip the cream with confectioners sugar until firm peaks form.
Assemble the Cake:
Cut the Cake: Once cooled, slice the cake into two even layers using a serrated knife. Brush both layers with the prepared syrup.
Layer with Cream and Strawberries: Spread a layer of whipped cream on the bottom cake layer, top with strawberries, then add more cream. Place the top layer on and cover the entire cake with the remaining cream.
Decorate: Use extra whipped cream and strawberries to decorate the top.
Chill and Serve: If using stabilized cream, chill the cake for 30 minutes. Otherwise, serve immediately or refrigerate for a few hours. Enjoy your Japanese Strawberry Cake!