Add the raspberries, sugar and lemon juice to a saucepan and heat it up until the raspberries are no longer frozen, have started to break down, and the resulting liquid has come to a bubble. Once bubbling, turn it down to a simmer.

Stir occasionally and with a rubber spatula mash down raspberries.

Let it simmer for 23-25 minutes or until the raspberry jam has thickened. To test this, add a bit of the raspberry jam to the back of a spoon and if you can make a line down the middle, with your finger, without it moving, it’s done.

Pour the jam into a shallow bowl, to let it cool down faster, and place it in the fridge, covered with plastic wrap. Let it cool down until room temperature or colder. Takes about 1 hour.

While the jam cools down, make the syrup. Place the sugar, water and raspberries in a small saucepan over high heat until the sugar dissolves and starts to boil.

Turn down the heat to a simmer and let it simmer for 3 minutes. Stir occasionally and break down the berries with a rubber spatula.

Once the time has passed, strain the syrup into a bowl using a fine mesh sieve and discard the raspberry kernels. Pour in the limoncello and let the syrup cool down to room temperature.

Once the raspberry jam and raspberry syrup is room temperature/cold, make the mascarpone filling. With a hand mixer or in a stand mix using the whisk attachment, cream the mascarpone, powdered sugar, lemon juice and vanilla paste until combined, about 30 seconds.

Scrape down the sides of the bowl and add the heavy cream to the mascarpone mixture and whisk it until it can hold a medium-stiff peak.

To assemble the tiramisu use a 27x20 cm (8x10.5 inch) baking dish or 23x23 cm (9x9 inch) or anything similar in that size.

Start by add a little bit of mascarpone cream to the bottom and even it out. Then dip the lady fingers into the raspberry syrup twice on each side.

Lay the lady fingers in a layer in the baking dish. Add half of the mascarpone cream and even it out into an even layer. Then add half of the raspberry jam and even it out.

Repeat the process, except for the raspberry jam, that will be added once the tiramisu is ready to be served.

Add plastic wrap over the mascarpone cream and let it set in the fridge for a minimum of 8 hours or preferably overnight.

Once ready to serve, add the remaining raspberry jam and spread it out in an even layer. Optionally decorate with fresh raspberries and lemon slices.