Preheat oven to 350 degrees. Grease an 8x8 baking dish and set aside.
In a small/medium mixing bowl, whisk together flour, oats, salt and baking soda. Add in 1/2 cup granulated sugar and 1/2 cup brown sugar and mix until well blended.
Add melted butter and vanilla to the flour mixture, then stir with a wooden spoon or spatula until fully combined and moistened.
With a light hand, press half of the mixture into a greased 8 by 8-inch baking dish. Place in the preheated oven and bake for 15 minutes.
While the crust is baking, combine 1/4 cup granulated sugar, 1/4 cup brown sugar, cinnamon, nutmeg, ginger, cloves and salt in a medium sized mixing bowl and whisk until fully blended.
Add in egg, egg yolk and vanilla and stir well. Mix in pumpkin and half and half and stir until combined and smooth. Pour the pumpkin mixture over the baked crust and return to the oven to bake for another 15 minutes.
Remove the dish from the oven and crumble the remaining crust mixture over top. Return to the oven to bake about 20 - 25 minutes longer or until the crust is starting to become golden. Remove from the oven and allow to cool for at least one hour before serving. Or, if you don’t care about crumbly bars, cut and serve warm!