Double-Decker Rhubarb Ice Cream Sandwiches

Preparation

1. Step 1

   Scrape seeds from vanilla bean into heavy medium saucepan; add bean. Add rhubarb (with juices if using frozen), 1 cup sugar, 2 tablespoons corn syrup and pinch of salt. Cover pan and cook over medium-low heat until rhubarb is tender, about 10 minutes. Cool; discard vanilla bean. Place rhubarb mixture in blender. Add raspberries with juices; purée mixture until smooth.

   Step 2

   Whisk egg yolks, 1/2 cup whipping cream, remaining 1/2 cup sugar and 2 tablespoons corn syrup in clean heavy medium saucepan to blend well. Stir mixture over medium-low heat until thick enough to coat spoon, about 7 minutes (do not boil). Remove from heat. Mix in 2 1/3 cups rhubarb-raspberry purée. Refrigerate custard until cold. Cover and refrigerate remaining rhubarb-raspberry purée for sauce.

   Step 3

   Process rhubarb custard in ice cream maker according to manufacturer's instructions. Freeze in covered container.

   Step 4

   Place 8 Pistachio Meringues on clean baking sheet. Top each meringue with scoop of rhubarb-raspberry ice cream; flatten ice cream to reach edge of meringue. Top each ice-cream-covered meringue with another meringue and another scoop of ice cream; flatten to reach edge. Top each with third meringue. Cover and freeze ice cream sandwiches until firm, about 2 hours. (Can be made 3 days ahead. Keep frozen.)

   Step 5

   Cut sandwiches in half. Place 2 halves, rounded sides down, on plates. Drizzle with reserved purée.