Peanut Butter Mousse:
1 1/4 dark brown sugar
1 cup whipped topping, (unwhipped), divided
3 large egg yolks
6 Tablespoons (3/4 stick) margarine
1 1/4 cups creamy peanut butter
Glaze & Sauce:
1 1/2 cups whipped topping, (unwhipped)
2 Tablespoons (1/4 stick) margarine
4 teaspoons , light corn syrup
12 ounces bittersweet or semisweet chocolate, chopped
1/2 cup coarsely chopped roasted salted peanuts, for garnish
1. Prepare peanut butter mousse: Whisk sugar, 1/2 cup topping, and yolks in a medium saucepan to blend. Place over medium heat and stir until sugar dissolves and sauce thickens, scraping down the sides occasionally. This should take about 6 minutes (do not boil). Transfer dark brown sugar mixture to a medium bowl and refrigerate until cold and very thick, at least 3 hours and up to 1 day. Stir mixture occasionally while refrigerating.
2. Line a 7 or 8 inch loaf pan with plastic wrap and leave a 2 inch overhang.
3. In a large bowl of an electric mixer, beat margarine until fluffy. Add peanut butter; beat until smooth. Beat in dark brown sugar mixture in 3 additions. In a medium bowl, beat remaining 1/2 cup of topping until peaks form. Fold whipped cream into peanut butter mixture in 2 additions. Transfer mousse to prepared pan. Refrigerate while preparing glaze.
4. Prepare glaze and sauce: Place topping, margarine, and corn syrup into a heavy medium saucepan. Simmer over medium heat, stirring often, until margarine is fully melted. Remove from heat. Add chocolate; whisk until melted and smooth.
5. Remove 1/3 cup glaze to a small bowl and cool to room temperature. Spread over mousse in pan. Cover loaf pan and freeze mousse overnight.
6. Chill remaining glaze in an airtight container until needed.
7. Place a cooling rack on a baking sheet. Turn mousse out of loaf pan onto rack, chocolate side down. Peel off plastic wrap. Remove glaze from the refrigerator and and place 1 1/3 cups glaze into a small saucepan. Stir over low heat until just warm and pour-able, but not hot. Gradually pour melted glaze over mousse, spreading to cover evenly. Use any glaze that drips onto baking sheet, if needed. Press chopped peanuts onto top of mousse. Transfer to platter and freeze until glaze is frozen, about 30 minutes.
8. To serve: Rewarm remaining glaze to use as sauce. Dip a large knife into hot water to warm the blade and wipe dry. Cut mousse crosswise into thin slices, rewarming and wiping blade dry before cutting each slice. Place mousse onto plates. Spoon some sauce alongside the mousse and serve.
Note: This mousse can be made up to 2 days in advance. Once glaze is frozen solid (step 7), cover mousse loosely and return to freezer.