Prepare the crust by combining graham cracker crumbs, brown sugar, and melted butter until evenly moistened. Press firmly into a 9-inch pie plate and refrigerate for at least 1 hour to set.

In a large bowl, beat softened cream cheese and creamy peanut butter until smooth. Gradually add powdered sugar and vanilla, mixing until fully incorporated. Whip heavy cream until stiff peaks form and fold into the peanut butter mixture.

Heat heavy cream for the ganache in a small saucepan until it steams, then whisk in semisweet chocolate chips until smooth. Pour the ganache over the peanut butter filling.

Cover the pie with plastic wrap and refrigerate for at least 4 hours to set, or freeze for 2 hours if you're short on time.