The first step is to very carefully separate the egg whites from the egg yolks. Make sure that not a drop of water, fat, or yolk get into the egg whites, or you won’t be able to beat the whites to a stiff peaks. Also, make sure that the mixing bowl, the whisk attachment or anything else that will touch the egg whites are very clean and dry, so no residual oil or fat is left behind to disturb or deflate the egg whites.
Combine the egg whites with a pinch of salt and using a hand mixer, beat the egg whites until it reaches a foamy consistency, then add the sugar in two batches and beat the whites until you can see the traces of the whisk on the surface. Continue to whisk the egg whites, add the egg yolks one at a time. You should get a fluffy mixture.
Next add the sifted flour and poppy seeds in 2-3 butches. Using a spatula mix them together until it reaches a smooth consistency. The last thing we need to add is the melted butter and mix again.
Using a kitchen scale, divide the cake batter between two 8-inch spring forms, lined with parchment paper. Carefully spread the batter and bake at 350 F degrees for about 35 minutes.Check the readiness with a skewer or a toothpick. Inserted into the cake it should come out dry. Let the cake cool in the baking pan for about 5 minute or so, then run a knife between the cake and the baking pan. Take the ring part off, invert the cake and carefully take off the parchment paper from the bottom. Let the cake cool down to room temperature, then cover each cake with plastic wrap and refrigerate for a few hours.
Pour the gelatin into water and mix well. Let it sit for 15 minutes.
In a heavy bottom saucepan, combine the strawberries, water, and sugar. Bring the mixture to a boil and cook for about 5 minutes, stirring occasionally.
Take off the heat, and using a hand blender, smash the strawberries. Next, we need to dissolve the gelatin by microwaving it for 15 seconds. Add the liquid gelatin to the strawberry sauce and mix well.
Now let’s prepare the baking ring. Spread a small amount of water on the outer edge of the ring and tighten with plastic wrap. I use a 7-inch baking ring. That way my filling will be slightly smaller than the cake and will be covered with cream cheese filling on the sides.
Pour the strawberry filling into the prepared baking ring and place in the freezer for a few hours.
In a heavy bottom saucepan, combine the lemon juice, sugar, lemon zest and egg. While constantly stirring, cook it on low heat for about 7 to 10 minutes.
Take the mixture off the heat and add the butter. Mix until the butter has dissolved. Dissolve the gelatin by microwaving for 15 seconds and add the liquid gelatin to the lemon sauce. Mix well.
Pour the lemon filling into the prepared baking ring and place in the freezer for a few hours.
Before making the cream cheese mousse let’s prepare all the other parts of the cake. Using a bread knife, cut off a thin layer of the brown crust off each cake. Place the first cake layer on the serving plate or a cake board. Put the adjustable baking ring around the first cake layer, place the cake collar inside the ring and adjust the ring so that it fits tight around the cake. Since my cake collar is not high enough, I used two pieces of Teflon mat about 5-inch wide. We also need to cut our frozen fillings out of the baking rings, by running a knife between the filling and the baking ring. Carefully push the filling down and take the ring off. Prepare the lemon filling the same way.
Start by microwaving the chocolate for 15 seconds then take the bowl out and give it a stir. Place the bowl back in the microwave and repeat the process of cooking for another 15 seconds, stopping, stirring and returning it to the microwave until the chocolate has melted. Dissolve the gelatin by microwaving it for 15 seconds and add the liquid gelatin to the melted chocolate. Mix them together.
Place the cream cheese in a mixing bowl, and using a hand mixer, whip it for about a minute. Add the mixture of white chocolate and whisk until combined well.
Place the cold heavy cream in a large mixing bowl and using a hand mixer whisk until soft peaks are formed. It should have a consistency of melted ice cream. Add the cream cheese mixture to the whipped cream and give it a quick whisk. Add the powdered sugar and mix it with a spatula. Transfer it into a piping bag.
Pipe the filling on top of the first cake layer, about half an inch thick. Spread evenly with a spatula or spoon. Take off the plastic wrap from the strawberry filling and place the filling in the middle of the cake filling.
Pipe the cream cheese filling in between the strawberry filling and baking ring, then on top of the strawberry filling. Spread it evenly with a spatula. Place the second cake layer on top and press gently with your hand.Repeat the process with the lemon filling. Cover the cake with plastic wrap and refrigerate for 4-6 hours or overnight. The next day, decorate the cake as you wish. I decided to make a second portion of strawberry filling, and instead of freezing it in the baking ring, I poured it on top of the cake and refrigerated until my top layer had set.*PAY ATTENTION to the changed amount of gelatin in the amount of the ingredients!To finish the cake, take off the baking ring and the cake collar. I also decorated the top of the cake with some piped flowers using mascarpone frosting.