Directions

1. 1

   Pour 1 cup of heavy cream and ½ cup sugar into a small saucepan. Set over medium-high heat and warm, stirring occasionally, until wisps of steam rise from the surface and the sugar is fully dissolved.

2. 2

   In a separate bowl, whisk the cornstarch together with the remaining ½ cup heavy cream until smooth and no lumps remain.

3. 3

   Slowly pour the cornstarch mixture into the hot cream, whisking constantly to incorporate smoothly. Reduce heat to low and continue whisking for 5 to 6 minutes until the mixture thickens enough to coat the back of a spoon.

4. 4

   Remove from heat immediately. Stir in the buttermilk, lemon juice, lemon zest, salt, and limoncello if using.

5. 5

   Pour the custard into a clean bowl. Place plastic wrap directly on the surface to prevent a skin from forming. Refrigerate for at least 2 hours, or preferably overnight.

6. 6

   While the custard chills, prepare the raspberry sauce. Combine the raspberries, 2 tbsp water, and any remaining sugar in a small saucepan. Set over medium-high heat and bring to a simmer, stirring occasionally.

7. 7

   Continue cooking for about 10 minutes, stirring from time to time, until the raspberries soften and break down completely and the mixture thickens slightly.

8. 8

   Pour the raspberry mixture through a fine-mesh sieve to remove seeds, pressing gently on the berries to extract the juice. Stir in the vodka or raspberry liqueur. Cover and refrigerate until ready to use.

9. 9

   When the custard is fully chilled, transfer it to your ice cream maker and churn according to the manufacturer's instructions until it reaches a soft-serve consistency.

10. 10

    Spoon alternating layers of gelato and raspberry sauce into a freezer-safe container. Run a skewer or butter knife through the mixture several times to create a swirled ripple effect.

11. 11

    Transfer to the freezer and chill until firm but scoopable, approximately 4 hours before serving.