Step 1
First, we need to make the puree. For this, you are going to need 1 pound of fresh strawberries and a food processor or a blender. Just cut them into pieces and allow the machine to do all the extra work until you have a smooth puree texture.
Step 2
The real problem with this is that people add this puree as-is into their cakes and it totally disrupts the liquid to flour ratio. Then you are forced to add more flour, making the cake dense. It is also not worth it, because the flavor is not there.
The ideal thing to do is to reduce this puree down on the stove. This will concentrate the strawberry flavor and get rid of all the extra water we do not need in our batter.
On high heat, stirring constantly, reduce the puree to half its size. You will end up with a very thick and very red mixture which is exactly what we need!
You will need to let the puree sit and cool. It is best to make it the day before and let it cool overnight in the fridge. If not, let a few hours go by before adding it to the batter.
Do not worry about the seeds, they will disappear completely in the baked cake.
Step 3
When you are ready to make the cake, preheat your oven to 350°F. Also, grease and flour 2 9 by 13-inch cake pans to avoid the cake sticking to them. You could use some parchment paper instead.
Step 4
Mix the dry ingredients in a bowl and set aside. These are the flour, baking powder, baking soda, and salt.
Step 5
In a stand mixer, cream the butter (it must be room temperature!) with the sugar until it is smooth and fluffy. This will take approximately 2 minutes. Do not forget to scrape the sides!
Step 6
Separate your eggs into 5 egg whites and 5 yolks.
Step 7
Add your egg whites to the butter and sugar and mix them until well combined on high speed. It will take another 2 minutes.
Step 8
Add in the sour cream with the vanilla extract and also mix until combined.
Step 9
At low speed, start adding your dry ingredients gradually. Make sure you do not end up with flour on your face!
Step 10
Do not stop mixing on low and, very slowly, add the milk. Once it is combined, stop mixing. It is very important you do not overmix the cake!
Step 11
Add in the strawberry puree and the food coloring (just 1 drop) if you so wish. Whisk until the batter is smooth. It will have a thick texture.
Step 12
Pour evenly into your 2 cake pans and get them inside the preheated oven for 25 minutes approximately. Check if they are done by inserting a toothpick in their center. If it comes out clean, then you can take them out.
Step 13
Let cool for 10 minutes and then take out of the pans. Leave them to cool on a rack. They need to be completely at room temperature before frosting them.
Step 14
While they are baking, make the frosting. Take the freeze-dried strawberries and process them into a powder. You need ½ cup of this.
Step 15
Again in the stand mixer (you could also use a hand mixer and a large bowl) beat the cream cheese on high speed for a minute until it is fluffy.
Step 16
Beat in the butter and mix on high until well combined.
Step 17
Add the powdered sugar, strawberry powder, 1 tablespoon of milk and vanilla extract. Then beat until the frosting comes together into a creamy mix. If you need to thin it out, add another tablespoon of milk.
Step 18
You are ready to frost and assemble your cake! Level the cakes with a serrated knife and place them on a stand. Then fill the cake up and cover it with the remaining frosting once the second layer is on.
Let it cool for an hour in the fridge before serving, so that it holds its shape. You can decorate with fresh strawberries!