Grease your baking dish and line it with parchment paper, leaving some overhang for easy extraction later if you want. Preheat your oven to 375℉.
In a mixing bowl, stir together the flour, brown sugar, baking soda, baking powder, cinnamon (or pie spice), and cloves. Add the melted butter and mix until you get a crumbly sort of dough.
Take a quarter of the dough and press it into the bottom of the baking dish, flattening it to make your bottom crust for the pie bars. Set the remaining three quarters aside.
In another bowl, beat together the pumpkin puree, sugars, pie spice, egg, and vanilla, until well combined. You can do this by hand or with a mixer, whatever you prefer.
Pour the pie filling over the prepared crust and spread it evenly. Crumble the remaining topping over the top.
Bake this for 32 minutes, or until the topping is golden. Let cool and enjoy with a bit of whipped cream or cool whip!