How to Make It
Prepare the crème anglaise: Whisk egg yolks together in a medium bowl, and set aside. Combine half-and-half and sugar in a medium saucepan. Scrape seeds from vanilla bean into half-and-half mixture, and cook over medium, stirring occasionally, until mixture begins to simmer (but not boil), about 15 minutes. Remove from heat; cover and let stand 15 minutes.
Whisk 1 cup of hot half-and-half mixture into egg yolks; slowly pour the yolk mixture into remaining half-and-half mixture. Cook over low, stirring constantly, until mixture thickens and coats the back of a wooden spoon, about 10 minutes. (Do not boil.) Remove pan from heat, and pour through a wire-mesh strainer into a medium metal bowl. Place the bowl inside a larger bowl of ice to help cool the mixture down. Stir occasionally until mixture is cool, about 30 minutes; cover and chill until ready to use.
Prepare the meringues: Preheat oven to 250°F. Line a baking sheet with parchment paper.
Beat egg whites with an electric mixer fitted with a whisk attachment on medium-high speed in a large metal bowl until foamy. Add cream of tartar and pinch of salt, and beat until combined. Add sugar, 1 tablespoon at a time, and beat on medium-high speed until incorporated after each addition. Continue beating until egg whites are shiny and form stiff peaks. Spoon meringue into 8 cloud-shaped mounds on prepared baking sheet.
Bake in preheated oven until a little firm but still springy and not browned, 1 1/2 to 2 hours. Remove meringues from oven, and cool completely, about 45 minutes.
Prepare the caramel: Cook sugar in a small, heavy saucepan over medium-high, whisking constantly, until sugar is completely melted and begins to brown. Reduce heat to medium-low, and cook until sugar is golden brown. Remove from heat. (The sauce will continue to cook in the pan. Be careful not to touch the caramelized sugar.)
Assemble: Divide the crème anglaise among 8 individual shallow bowls or dessert plates. Place 1 meringue cloud in each bowl. Pour caramel over meringues, or dip a fork into the caramel, and drizzle over meringues. (If the sauce begins to thicken, simply reheat it over low until it returns to drizzling consistency.) Garnish with fresh raspberries, if desired.