Crust and Topping
1 1/4 cups all-purpose flour
1 1/4 cups quick or old-fashioned oats
1/2 tsp salt
1/2 tsp baking soda
1/2 cup granulated sugar
1/2 cup packed light-brown sugar
3/4 cup coconut oil (or butter), melted
1 tsp vanilla extract
1 tablespoon coarse sugar, optional
Pumpkin Pie Filling
1/4 cup granulated sugar
1/4 cup packed-light brown sugar
1 tsp cinnamon
1/2 tsp nutmeg (or allspice)
1/4 tsp ginger
1 pinch ground cloves
1/4 tsp salt
1 large egg
1 large egg yolk
1/2 tsp vanilla extract
1 1/4 cups pumpkin puree
1/3 cup half and half
Preheat oven to 350 F. Prepare an 8×8-inch baking pan by lining it with parchment paper, set aside.
In a medium bowl, whisk together the flour, oats, salt, and baking soda. Whisk is the sugars and stir until there are no lumps. Stir in the melted coconut oil and vanilla until combined. Dump half of the mixture into your prepared pan and press it down evenly over the bottom of the pan. Bake for 15 minutes.
Meanwhile, prepare the filling by stirring together the sugars, spices, and salt. Whisk in the egg, egg yolk, and vanilla. Stir in the pumpkin puree and then stir in the milk. Pour the filling over the baked crust and continue baking for 15 more minutes.
Remove from the oven and sprinkle on the remaining half of the crumb topping (also sprinkle on the coarse sugar, if desired). Bake for 20-25 minutes on a top rack to prevent the bottom crust from burning. Remove from the oven when the crumb topping is slightly brown and the filling is mostly set (it will still have a jiggle to it). Allow bars to cool for one hour at room temperature and then chill completely in the refrigerator. Once chilled, cut the bars and enjoy! Serve plain, topped with whipped cream, or with a scoop of vanilla ice cream and a dash of cinnamon. Store the bars covered in the refrigerator.