Directions for the Vanilla infused Cream
 

• Note, The cake batter recipe needs 385 grams of vanilla-infused cream, but If you warm only 385 grams, you won’t have enough because you will lose some to evaporation; that´s why in the case of this cake, heat 425 grams of heavy gram with the vanilla bean/seeds as described below. If you are using vanilla bean paste, you don't need to warm the cream, and you need only 385 grams of heavy cream, just make sure you use heavy cream that is at room temp, add the vanilla bean paste, give a quick whisk, and set aside for now.
   
• For the Vanilla infused cream, Use a sharp knife to split the fresh vanilla bean lengthwise and scrape the vanilla caviar seeds into a medium saucepan, put the pod in the saucepan as well.
   
• Pour heavy cream into the saucepan, and give it a little whisk.
   
• Place the saucepan over low-medium heat until warm but not boiling.
   
• Remove from heat, cover, and let steep at room temp for 1 hour if time permits (optional); otherwise, proceed as directed.

Directions for the vanilla cake layers
 

• Preheat the oven to 325F° (165C°) for 30 minutes before baking.
   
• Grease a  32 x 25 cm (13 x 10-inch) sheet pan, cover the bottom and side with parchment paper, and set it aside for now.
   
• Bakers note; Working with semi-cold butter produces a better cake texture; if the butter is too soft, it essentially melts into the flour, which can result in a greasy cake. The butter needs to be pliable (slightly softened) but cool. Take it out of the fridge for about 20 minutes before you bake this cake. The right temperature is 18C°/64,4F°. The best way to know for sure is by using a digital thermometer. 
   
• Bakers note; However, the egg whites and cream should be at room temp about 23C°/73,4.F°; if yours are too cold, the cake batter will go from smooth and creamy to looking split and clumped. The cake might turn out ok, but the texture will be affected and may not be as tender and moist as you like.
   
• Sift the 305-gram cake flour into a bowl of a stand mixer, and add 4 teaspoons of baking powder, a pinch of salt, and 400-gram superfine sugar.
   
• Attach the whisk attachment, and mix at low speed for about 1 minute to combine everything.
   
• Add 165-gram butter one piece at a time, about every 10 seconds; take your time when you do this step. Once all of the butter is added, the mixture should resemble almond flour, and when you run your hands through it, it feels kind of sandy, and there should be no large lumps of butter left.
   
• If you, at this point, still have large lumps of butter, try to break them up with your beautiful hands and continue mixing on low until the flour and butter mixture resembles almond flour/ feels sandy.
   
• Discard the vanilla bean from the heavy cream ( make sure you squeeze out all of the gooey vanilla seeds and add them back into the cream), give it a quick whisk, and make sure you have 385 grams.
   
• *Note when it is time to add the vanilla-infused cream, you want to add the cream a little at a time and make sure you’re maintaining the smooth emulsion the whole time. Make sure the cream is at room temp and add it in small increments and mix on medium-low speed until smooth. You don't want to add the cream at once, or the fat won't be able to trap it, and the batter will look curdled.
   
• With the mixer on low, slowly pour in the 385-gram vanilla-infused cream in small increments, a little at a time, then continue mixing on medium speed (speed 4 on KitchenAid) for two full minutes to develop the structure. Set a timer! Do not overmix for just 2 minutes, not any longer! 
   
• The batter should have gained volume at this point and have a texture like a thick buttercream, and all the ingredients should be incorporated at this stage. If you don’t mix it for two full minutes, your cake could be under-mixed and collapse in the center and won't be as tender and fluffy as mine.
   
• Stop the mixer and scrape down the side and bottom of the bowl, remove the whisk attachment, and shake out the excess batter that is collected inside. From this point, you need to mix as lightly and little as I mention.
   
• A Note from me before you add the egg whites! As most cakes are highly prone to overmixing, when you reach this step where you add the egg whites, it is very important to mix lightly. This is because your cake batter will become tough if you work it to the point that the gluten in the flour starts to form. Make sure the egg whites are at room temp. Add the egg whites in small increments to the cake batter slowly and carefully. This process simply cannot be rushed, as you are emulsifying a liquid into fat; if not done gradually, you risk “breaking” the batter, and you see the mixture separate. 
   
• Attach your whisk attachment again, starting at low speed, slowly stream the 210-gram egg whites to the cake batter in four/five separate parts, beating on low speed for only 20 seconds each time ( not any longer!) after each addition to incorporate the ingredients and strengthen the structure. Stop the mixer after each addition of egg whites, and scrape down the side and bottom of the bowl also, remove the whisk attachment and shake out the excess batter that is collected inside. Be careful not to overmix, or the crumb will be dry.
   
• Stop the mixer and scrape down the side and the bottom fold once or twice to ensure the batter at the bottom of the mixing bowl is incorporated. 
   
• Pour and spread the vanilla cake batter into the prepared pan.
   
• Bake in the center of the oven until a cake tester/toothpick inserted in the center of the cake comes out with just a few moist crumbs. It takes about 25 to 30 minutes. ( mine took 30 minutes)
   
• Begin checking for doneness at 25 minutes. To test for doneness, insert a toothpick into the center of the cake, if it comes out clean, it´s done. Allow the cake to cool completely in the pan set on a wire rack. 
   
• The Vanilla sheet cake must be completely cool before frosting the cake.
   
• You can also very carefully invert the vanilla sheet cake once fully cooled and place it on a cake board as I did.
   
• This step is optional. I like to trim off the top crust with a serrated knife before I frost the cake with the Vanilla fluff.
  
   

Marshmallow Fluff

• Baker's note: For best results, use pasteurized egg whites, if using fresh store the egg whites in the fridge for a couple of days before using them, chilled egg whites as the proteins are tougher and break down more slowly. This creates a stronger meringue once a pinch of cream of tartar and 3 tablespoons of sugar are added. Whip the egg whites to reach maximum volume by the time the sugar syrup is ready. Make sure to cook the cooked syrup into the egg whites slowly to prevent lumps. I recommend removing the saucepan with the sugar syrup from the heat when it reaches 116.5°C, as the saucepan is still hot, and this causes the temperature to rise to 117°C, be aware that once the sugar syrup passes 110°C, it quickly rises to 117°C/242.6°F.
   
• If using a fresh vanilla bean; "Using a knife, make a lengthwise cut in the vanilla bean and scrape out the seeds. Set them aside for now."
   
• In a 20 cm (8-inch) wide saucepan, combine 225 grams of superfine sugar, 120 grams of glucose, and 90 grams of water. Before bringing the sugar syrup to a boil, combine/stir with a clean finger until the sugar is evenly moistened and looks sandy, and no dry sugar pockets left. When the sugar melts and starts bubbling, use a clean pastry brush to brush down the pan sides with cold water to remove sugar crystals. Continiou to cook over medium-high heat, Do not stir the sugar syrup while it’s boiling until the thermometer reads 117°C/242.6°F. Be careful not to go below or above as it will affect the marshmallow fluff texture.
   
• Meanwhile, clean the inside of a stainless steel or glass bowl and the whisk attachment with a paper towel moistened with lemon juice. This step eliminates grease traces, which can affect the marshmallow foam.
   
• In the mixer's bowl, combine 150 grams of egg whites, 3 tablespoons of superfine sugar, and a pinch of cream of tartar. Start the mixer at a low speed.
   
• As the temperature of the sugar syrup approaches,  increase the mixer speed to medium-high. Whip the egg whites until they have stiff peaks but remain shiny and soft. Monitor the egg whites to prevent over-whipping. Ensure the sugar syrup reaches 117°C/242.6°F., and the egg whites have reached maximum volume.
   
• Bakers note; When pouring the sugar syrup into egg whites, make sure you pour it along the edge of the mixing bowl, avoiding direct contact with the whisk. This prevents the syrup from sticking to the side of the bowl, ensuring a stable marshmallow fluff foam.
   
• When the sugar syrup reaches the right temperature, pour the warm sugar syrup slowly into the egg whites in a thin steady stream, while whisking at high speed. 
   
• After all the sugar syrup has been incorporated into the egg whites, continue to whisk at high speed until the mixture cools down the marshmallow fluff is thick, glossy, and holds a firm peak. Mix for 10-20 minutes to achieve this consistency. The mixture should be around 35°C/95°F. when done. If you want a denser marshmallow foam, you can stop whisking just before it reaches 30°C/86°F. to incorporate less air.
   
• If desired, mix in the seeds from 1 vanilla bean at the end for an additional 30 seconds

• Scoop as much marshmallow Fluff on top of the vanilla sheet cake.
   
• Cover the entire cake quickly with the vanilla fluff, use the back of a spoon or an offset spatula to quickly swirl the vanilla fluff over the cake.
   
• Drizzle the top with coconut unsweetened shredded coconut. (optional) and place some fresh cherries on top ( if in season) 
   
• Use a serrated knife to slice your cake, and enjoy it is so delicious.
   
• For maximum freshness and deliciousness enjoy immediately.
   
• Store leftover cake slices under a cake dome, the frosted vanilla sheet cake slices will keep for up to 48 hours at room temperature, without the frosting this cake stays soft if covered at room temp for 3 days.