Chocolate Peanut Butter Cheesecake Bars

For the Crust - Line an 8-inch square baking pan with aluminum foil, leaving a 1-inch overhang on all sides.

For the Crust - In a food processor, process chocolate sandwich cookies until finely ground, about 12 to 14 pulses. Add butter and pulse until well combined and evenly moistened, 4 to 6 pulses. Using a straight-sided measuring cup or the bottom of a glass, firmly press cookie mixture evenly over bottom of prepared pan. Chill, uncovered, in freezer while preparing filling.

For the Cheesecake - In a large bowl with a hand-held electric mixer, or in the bowl of a stand mixer fitted with whisk attachment, beat cream cheese on medium speed until smooth and creamy, 2 to 3 minutes, scraping sides of bowl as needed. Add confectioners' sugar, peanut butter, and vanilla, and beat on medium speed until smooth and combined, about 1 minute.

For the Cheesecake - In a separate large bowl, whisk cream by hand until stiff peaks form, 2 to 3 minutes. Fold whipped cream into cream cheese mixture in two additions until combined; spread evenly over prepared crust. Loosely cover with plastic wrap and refrigerate until set, about 4 hours.

For the Topping - After peanut butter mixture has set, fill a medium saucepan with 1 inch of water, bring to a boil over medium-high heat, then reduce to a simmer. In a medium heatproof bowl, add chocolate, cream, and corn syrup. Place bowl with chocolate over simmering water and cook, stirring frequently with rubber spatula, until melted and smooth, 2 to 3 minutes. Let cool, off-heat, for 5 minutes. Spread chocolate mixture evenly over chilled cheesecake bars, then sprinkle evenly with peanuts. Refrigerate, uncovered, until firm, about 1 hour.

For the Topping - Using overhanging aluminum foil as handles, lift cheesecake from pan. Using a small knife or small offset spatula, loosen sides of cheesecake from aluminum foil. Cut into 16 (2-inch) squares, wiping knife clean between each cut. Garnish with flaky sea salt, if using. Serve.