Start by grating the outer part of a lemon using a fine grater or zester, setting the zest aside for the final decoration on the tiramisu.

In a medium-sized pot, combine 1 liter of water with 300g of sugar. Heat the pot over medium-high heat, until the sugar completely dissolves into the water.

Once the sugar has dissolved, introduce the juice of 3 lemons into the pot, using a strainer to prevent any seeds from get into the syrup.

With a potato peeler, carefully remove the outer peel of a lemon, ensuring to avoid the bitter white part, and add it to the water.

Allow the water, infused with sugar, lemon juice, and peel, to boil for a minimum of 5 minutes.

After 5 minutes, switch off the heat and incorporate 100ml of Limoncello into the syrup, gently stirring it in.

Next, strain the lemon-infused syrup into a bowl to filter out any lemon peels. Let the syrup cool at room temperature for about an hour before using it.

The first step is to separate the egg whites from the yolks and add each to a large bowl.

Using a hand mixer, first mix the egg yolks and gradually add 3 tablespoons of sugar. Continue mixing until a creamy texture is achieved.

Next, add the mascarpone and mix once until thoroughly combined using the hand mixer.

Using a strainer, squeeze the juice of a lemon into the cream, and stir thoroughly.

Proceed to beat the egg whites next again, using the hand mixer. Gradually add the remaining sugar.

Once these are fluffy, fold the egg whites with the mascarpone cream mixture.

With a spatula, gently combine the two until you get a smooth, velvety cream.

Now, pour in generous amount of Limoncello for an added burst of flavor - the amount will depend on how strong you want it. Mix through using a spatula.

Let the cream rest in the fridge for approximately 20-30 minutes.

Now it's time to assemble the tiramisu, so get your Pyrex dish, Savoiardi biscuits, lemon syrup and mascarpone cream.

Dip the biscuits in the syrup for 3 seconds, let the excess drip off, and line them up in the Pyrex.

Once the first layer is complete, add mascarpone cream on top, spreading it across every biscuit using the back of a spoon.

Finish the first layer by grating white chocolate over the top. Then add some of the lemon zest prepared earlier.

Now, repeat all the previous steps to create the second layer.

Decorate the surface with extra grated white chocolate and the remaining lemon zest - this will be your top layer.

Cover the tiramisu with plastic wrap and let it rest in the fridge for at least a day, up to a maximum of four.