1. Make the Raspberry Syrup: Place raspberries and water in a saucepan over medium-high heat. Mash the berries and bring to a simmer. Reduce heat and simmer for 2 minutes.

2. Strain the mixture through a fine mesh sieve, pressing with the back of a spoon to extract juice. Discard seeds.

3. Return the raspberry juice to the pan, add sugar and lemon juice, and simmer for 4–5 minutes to reduce slightly. Chill completely.

4. Make the Filling: Whip heavy cream to stiff peaks. In a stand mixer with paddle attachment, combine mascarpone, sugar, 3/4 cup raspberry syrup, and vanilla. Mix until combined.

5. Add 1 cup whipped cream to the mascarpone mixture and beat until incorporated. Fold in remaining whipped cream gently.

6. Assemble the Tiramisu: Dip ladyfingers in raspberry syrup one at a time and layer them in an 8-inch square dish.

7. Spread half the mascarpone filling over the ladyfingers. Grate half of the white chocolate on top.

8. Add another layer of soaked ladyfingers. Spread most of the remaining filling on top.

9. Transfer the last portion of filling to a piping bag and pipe over the top layer. Grate the remaining white chocolate over the dessert.

10. Cover and refrigerate for at least 6 hours, preferably overnight, before serving.