Prep the pan. Line a 9x9-inch baking pan with parchment, leaving overhang for easy lifting.
Preheat the oven to 350°F (175°C).
Mix the crust. In a bowl, whisk almond flour, coconut flour, sweetener, cinnamon, and salt. Stir in melted butter and vanilla until a damp, sandy dough forms that holds when pressed.
Press and par-bake. Press the crust evenly into the lined pan. Dock with a fork a few times.
Bake for 10–12 minutes until just set and lightly golden at the edges. Cool for 5 minutes.
Make the filling. In a large bowl, whisk pumpkin puree, eggs, cream, sweetener, vanilla, spices, and salt until smooth. Taste and adjust sweetness or spice if needed.
Fill and bake. Pour the filling over the warm crust.
Smooth the top. Bake 30–38 minutes, until the center is mostly set with a slight jiggle and a knife near the center comes out mostly clean.
Cool completely. Let the pan cool on a rack for at least 1 hour, then refrigerate 3–4 hours to fully set. This keeps the slices neat.
Slice and serve. Lift the bars out using the parchment.
Cut into 12–16 squares with a sharp knife, wiping the blade between cuts. Top with a dollop of whipped cream and a sprinkle of pecans, if you like.