Creamy, pumpkin-spiced bars on a toasty pecan–graham cracker crust, reminiscent of classic pumpkin pie but simpler and irresistibly smooth with a subtle warm lift from freshly ground black pepper.
Preheat oven to 350°F (177°C). Line a 9×13-inch baking pan with parchment paper, leaving overhang for easy removal.
Make the crust: In a food processor, pulse graham crackers (or crumbs) and pecans into crumbs (a few larger nut pieces are OK). Add granulated sugar and melted butter; pulse to combine.
Press crust mixture firmly into the bottom and slightly up the sides of the prepared pan. Pre-bake for 12 minutes. Leave oven on.
Make the filling: Using a mixer with whisk attachment or a hand whisk, beat all filling ingredients together until smooth.
Pour filling into the warm crust. Bake 40–50 minutes, or until the center is set and no longer jiggly.
Remove from oven and cool completely on a wire rack. Once cool, cover and refrigerate at least 1 hour and up to 3 days.
Lift chilled slab out of the pan using the parchment overhang and cut into squares. Serve chilled, topped with whipped cream and chopped pecans if desired.
Store leftovers covered in the refrigerator for up to 1 week.