Step 1

Pour about 1/4 cup half and half in one small bowl and 2 tablespoons in another. Use a fork to whisk cornstarch into the first bowl until no lumps remain, and sprinkle gelatin in second bowl. Add remaining half and half to a saucepan along with vanilla bean, sugar, and salt. Bring to a boil, then turn off heat, cover, and let steep for one hour.

Step 2

Remove vanilla bean (reserving for another use) and whisk in cornstarch slurry. Heat dairy on medium heat, whisking frequently, until a custard forms and a swiped finger leaves a clean line. Turn off heat, taste for seasoning, then stir in Scotch and gelatin mixture. Whisk until gelatin fully dissolves. Transfer to an airtight container to chill, four hours to overnight. The custard will set into a wobbly gel.

Step 3

Churn in an ice cream maker until ice cream has the texture of soft serve and is not at all runny. Eat immediately, or chill in freezer in an airtight container. To regain soft serve texture, let ice cream thaw to the verge of melting after freezing.