Step 1

1 Spray an 8-inch square baking pan with nonstick cooking spray and line it with parchment paper, leaving enough overhang on the sides to form a sling that you can use to lift the slab out later

Step 2

2 Make the peanut butter layer: In the bowl of a stand mixer fitted with the paddle attachment, or using a large bowl and a handheld mixer, combine the graham cracker crumbs, confectioners' sugar, melted butter, peanut butter, cream cheese, vanilla and salt on medium-low speed until well blended

Step 3

3 Pat evenly into the prepared pan

Step 4

4 Refrigerate until lightly set and cool to the touch, about 20 minutes

Step 5

5 Make the chocolate layer: In a medium, microwave-safe bowl, combine the chocolate chips and peanut butter

Step 6

6 Microwave on high in 30-second bursts, stirring well after each interval, until the mixture is melted and smooth

Step 7

7 Let cool slightly, then spread evenly over the peanut butter layer

Step 8

8 Sprinkle with flaky sea salt, if desired

Step 9

9 Refrigerate until firm, at least 1 hour

Step 10

10 Using the parchment handles, transfer the slab from the pan to a cutting board, and cut into fingers