Let 8 ounces cream cheese sit at room temperature until softened, about 45 minutes. Meanwhile, line an 8x8-inch baking pan (about 2 inches high) with 2 sheets of parchment paper, positioning them perpendicular to each other, so that the parchment hangs about 2 inches over all 4 sides of the pan to form a sling.

Place 1 (3.9-ounce) package instant chocolate pudding mix and 1 ½ cups cold milk in a large bowl. Whisk until dissolved and the mixture is slightly thickened, about 2 minutes. Let sit to thicken while you prepare the crust and other layers.

Place 6 tablespoons unsalted butter in a small microwave-safe bowl. Microwave on HIGH until melted, 40 to 60 seconds.

Set aside 3 cookies from 1 (about 13-ounce) package crunchy chocolate chip cookies for garnish. Break the remaining crunchy chocolate chip cookies into coarse pieces with your hands and place in the bowl of a food processor fitted with the blade attachment. Pulse until fine crumbs form, 12 to 15 (1-second) pulses (about 2 ¾ cups). (Alternatively, place the cookies in a sealed zip-top bag and crush with a rolling pin into fine crumbs.)

Drizzle the butter over the cookie crumbs. Add ¼ teaspoon of the kosher salt. Pulse until it resembles wet sand and holds together when squeezed, about 5 (1-second) pulses. (If making by hand, stir the crumbs, melted butter, and salt together in a medium bowl.) Transfer the mixture into the pan. Use the bottom of a measuring cup or your fingers to press the crumbs into an even layer, making sure to reach the edges and fill the corners.

Place 1 ½ cups cold heavy cream, ¼ packed cup of the brown sugar, and 1 teaspoon vanilla extract in the bowl of a stand mixer (or large bowl if using an electric hand mixer). Beat with the whisk attachment on high speed until stiff peaks form, 2 to 4 minutes. Transfer to another bowl if using a stand mixer.

Place the cream cheese, remaining ½ cup packed brown sugar, 1 teaspoon vanilla extract, and remaining ¼ teaspoon kosher salt in the bowl of the stand mixer (no need to wipe clean). Beat with the whisk attachment on medium speed, scraping down the sides of the bowl with a flexible spatula halfway through, until light and very fluffy, about 3 minutes total. Add 1 cup of the whipped cream and ⅓ cup of the miniature chocolate chips, and gently fold together with a flexible spatula until just combined.

Dollop the chocolate pudding over the crust and spread into an even layer. Dollop the cream cheese mixture over the chocolate pudding and spread into an even layer. Dollop the remaining whipped cream over the cream cheese mixture and spread into an even layer. Cover and refrigerate for at least 4 hours or up to overnight.

When ready to serve, crumble the reserved cookies directly over the top of the delight, then sprinkle with the remaining 2 tablespoons miniature chocolate chips. Grasping the excess parchment, transfer the slab to a cutting board. Cut into 12 pieces, wiping the knife between each cut for cleaner cuts.