Spray a 13 x 9” baking pan with nonstick cooking spray. Line the length of the pan with parchment paper that extends approximately 1 inch over the long sides of the pan. Spray parchment with nonstick cooking spray.
In a medium bowl, whisk together the flour, baking powder and salt. Set aside.
In the bowl of an electric mixer, using the paddle attachment, cream the butter and sugar until light.
Crack eggs in a liquid measuring cup. Add both extracts and zest into eggs and blend with a small whisk or fork.
On low speed, add eggs, one at a time, blending in each egg before adding the next.
On low speed, add one third of the dry ingredients and mix until well blended.
Add one half of the milk followed by another third of the dry ingredients.
Stop the mixer and scrape down the sides of the bowl using a rubber spatula.
On low speed, add the remaining milk followed by the remaining third of the dry ingredients.
Blend well, stopping the machine as needed to scrape down the sides of the bowl.
Pour batter into prepared pan spreading evenly using a small offset spatula.
Bake cake for approximately 45 minutes or until a small knife inserted into the center comes out clean.
Allow to cool completely.
Make Strawberry filling while cake is cooling.
Make Strawberry Filling:
In a small bowl, whisk together cornstarch and both juices until well blended.
In a medium saucepan, bring the strawberries, sugar, citrus juice and corn starch mixture to a boil. Stir gently and constantly with a large spoon.
Once the mixture has thickened, remove from the heat. Pour the topping into a heatproof bowl and allow to cool over an ice water bath.
Make Topping:
In the bowl of an electric mixer using the whip attachment on medium speed, cream mascarpone and butter until light and fluffy.
On low speed, add confectioners’ sugar, zest and vanilla and blend until well combined.
Assemble the Cake:
Using the end of a wooden spoon with a round handle, poke holes approximately 1 inch apart all over cooled cake in rows.
Spread cooled filling over cake with a spoon or offset spatula.
Spread topping over the filling, using an offset spatula.
Garnish with strawberry fans or sliced strawberries and lemon zest, if desired.
Chill for approximately 1 hour or more to allow filling to seep into holes in cake.