For chocolate bottom layer, line 12 muffin cups with paper liners and coat with non-stick cooking spray. In a small saucepan, heat ¼ cup cream over medium heat just until hot. Remove from heat and whisk in 1 cup chopped semi-sweet chocolate. Distribute melted chocolate evenly between muffin cups and refrigerate for 15 minutes to allow the bottom chocolate layer to harden.
For the peanut butter layer, in a microwave-safe dish, melt peanut butter and butter together. Stir in graham cracker crumbs, sugar, vanilla extract and salt. Place a few tablespoons of peanut butter mixture over hardened chocolate, filling the muffin cup ¾ of the way up. Refrigerate for 15 minutes more to harden.
For the top layer of chocolate, in a small saucepan, heat ¼ cup cream over medium heat just until hot. Remove from heat and whisk in ¾ cup chopped semi-sweet chocolate. Distribute melted chocolate on top of the peanut butter layer. Garnish with caramelized peanuts. Chill until firm, at least 30 minutes before serving.
For the caramelized peanuts, combine peanuts, sugar and water in a small saucepan over medium heat. Stir continuously, until peanuts turn an amber color without burning them. Remove from heat, spread out on parchment paper, sprinkle with salt and let cool. Break into pieces and garnish peanut butter cups.
Yield: 12 peanut butter cups