Step 1: Make the Cake Layers
Preheat oven to 350°F (175°C). Grease and flour two 9-inch cake pans.
In a medium bowl, whisk together flour, baking powder, and salt.
In a large bowl, beat butter and sugar until light and fluffy.
Add egg whites one at a time, beating well after each.
Stir in vanilla.
Alternate adding flour mixture and milk, beginning and ending with flour.
Divide batter evenly between pans and bake 25–30 minutes or until a toothpick comes out clean.
Cool in pans for 10 minutes, then transfer to wire racks to cool completely.

Step 2: Make the Bavarian Cream
Sprinkle gelatin over cold water and let bloom for 5 minutes.
In a saucepan, heat milk over medium heat until just steaming (don’t boil).
In a separate bowl, whisk egg yolks and sugar.
Slowly pour warm milk into yolks, whisking constantly to temper.
Return mixture to the saucepan and cook over low heat, stirring until it thickens slightly (do not boil).
Remove from heat and stir in gelatin mixture and vanilla. Let cool to room temperature.
Whip heavy cream to soft peaks and fold into the cooled custard. Chill in the fridge for 20–30 minutes to thicken slightly.

Step 3: Assemble the Cake
Place one cake layer into the bottom of a springform pan (or on a cake plate with a cake ring).
Spread the Bavarian cream evenly over the cake.
Top with the second cake layer and press gently to level.
Chill in the refrigerator for at least 4 hours or overnight to fully set.

Step 4: Decorate & Finish
Carefully remove the springform ring or cake ring.
Dust the top with a generous amount of powdered sugar to create a snowy finish.
Pipe or spoon whipped cream around the edges.
Top with white chocolate curls, coconut flakes, or mint leaves if desired.

Step 5: Slice & Serve
Slice with a clean, sharp knife (wipe between cuts for neat slices).
Serve chilled for the best texture and flavor.