01 -
Preheat oven to 350°F. Line an 8x8 or 9x9 inch pan with foil, leaving an overhang on two sides. Lightly grease the foil with nonstick spray. Beat butter and brown sugar using a mixer until creamy. Add flour and salt, mixing until just combined into a crumbly texture. Press mixture firmly into the pan’s bottom and bake for 10 minutes.
02 -
Whisk together sugar, pumpkin pie spice, cinnamon, and salt. Add pumpkin puree, eggs, egg yolk, half and half, and vanilla extract; whisk until smooth. Pour filling evenly over the pre-baked crust.
03 -
Bake bars until filling is mostly set but center slightly jiggles: about 45-55 minutes for 8x8 inch pan, or 25-35 minutes for 9x9 inch pan. Cool pan on wire rack to room temperature, then refrigerate until fully chilled.
04 -
In a small saucepan, combine brown sugar, butter, and salt. Simmer for 2 minutes, whisking frequently. Add half and half while whisking constantly. Simmer one additional minute without boiling. Remove from heat and fold in chopped pecans. Let cool to room temperature until thickened, then pour over bars if desired.