01 -
Add raspberries, sugar and lemon juice to a saucepan and heat until raspberries thaw, break down, and the mixture bubbles. Reduce to a simmer, stirring occasionally and mashing raspberries with a rubber spatula.
02 -
Simmer for 23-25 minutes until thickened. Test by placing a bit on the back of a spoon - if you can draw a line through it without the jam running, it's done. Transfer to a shallow bowl, cover with plastic wrap, and refrigerate until cool (about 1 hour).
03 -
While jam cools, combine sugar, water and raspberries in a small saucepan over high heat until sugar dissolves and mixture boils.
04 -
Reduce heat and simmer for 3 minutes, stirring occasionally and breaking down berries with a rubber spatula.
05 -
Strain syrup through a fine mesh sieve into a bowl, discarding raspberry seeds. Add limoncello and let cool to room temperature.
06 -
Once jam and syrup have cooled, beat mascarpone, powdered sugar, lemon juice and vanilla paste until combined, about 30 seconds.
07 -
Scrape down bowl sides, add heavy cream to mascarpone mixture, and whisk until medium-stiff peaks form.
08 -
Spread a thin layer of mascarpone cream on the bottom of your dish. Dip ladyfingers in raspberry syrup (twice on each side) and arrange in a single layer.
09 -
Spread half the mascarpone cream in an even layer over ladyfingers, then add half the raspberry jam in an even layer.
10 -
Repeat with another layer of dipped ladyfingers and remaining mascarpone cream (reserve remaining jam for serving).
11 -
Cover with plastic wrap and refrigerate for at least 8 hours or overnight.
12 -
Before serving, spread remaining raspberry jam in an even layer on top and decorate with fresh raspberries and lemon slices if desired.