Hot-Tin-Roof-Sundae

Ingredients

• 4 ounces bittersweet chocolate 60% chopped (preferably cocoa)
• 0.1 teaspoon coarse kosher salt 
• 12 tablespoons cacao nibs divided
• 6 tablespoons plus light
• 1 tablespoon cornstarch 
• 0.3 teaspoon cream of tartar 
• 3 large egg yolks 
• 5.5 cups heavy whipping cream chilled
• 3 cups milk 2% reduced-fat ()
• 6 tablespoons sugar 
• 2 tablespoons butter unsalted ()
• 0.5 teaspoon vanilla extract 
• 0.3 cup water 

Equipment

• bowl
• frying pan
• sauce pan
• whisk
• pastry brush

Directions

1. Stir first4 ingredients in heavy medium saucepanover medium heat until sugar dissolves,occasionally brushing down pan sideswith wet pastry brush. Increase heat andboil until syrup is deep amber, swirlingpan occasionally, about 10 minutes. Turnoff heat.
2. Add cream and butter (mixturewill bubble up). Stir until any caramelbits dissolve. Stir in salt and vanilla.
3. Addchocolate; stir until melted and smooth.DO AHEAD: Can be made 1 week ahead.
4. Transfer sauce to medium bowl; coverand chill. Rewarm before using.
5. Bring milk, 6 tablespoonscocoa nibs, sugar, and corn syrup justto boil in heavy medium saucepan overmedium heat, stirring until sugar dissolves.
6. Remove from heat; cover. Steep 20 minutes.
7. Whisk egg yolks and cornstarch inmedium bowl until blended; graduallywhisk in warm milk mixture. Return custardto same saucepan. Cook over medium heat,stirring constantly, until custard thickensand just begins to boil, 2 to 3 minutes.Strain custard into large bowl; discardnibs.
8. Whisk in cream and coarse salt. Chillcustard until cold.
9. Process custard in ice cream makeraccording to manufacturer’s instructions.
10. Transfer to container; mix in remaining6 tablespoons cocoa nibs. Cover and freezeat least 6 hours and up to 2 days.
11. For each sundae, place 2 scoops icecream in short tumbler; spoon warm sauceover.
12. Sprinkle with Chili-Lime Peanuts.
13. * Bits of shell-roasted cocoa beans;available at many specialty foods storesand from chocosphere.com.