Preheat oven to 350 F degrees. Grease a 9x13 inch baking pan with cooking spray or butter.
For Crumb Topping
In a medium size bowl, combine the rolled oats, flour and brown sugar. Using a pastry blender cut in the butter until pea-sized. Stir in the pecans.
For Pumpkin Cake
In a large bowl combine the flour, baking soda, cinnamon, pumpkin pie spice and salt. Set aside.
In another large bowl or in the bowl of your mixer, beat the brown sugar, granulated sugar, melted butter and eggs on medium for about 2 minutes until well combined.
Add the pumpkin and mix for another 30 seconds. Add the flour mixture and beat on low until well combined.
Spread the batter in the prepared baking pan then top with the crumble topping.
Bake for about 55 minutes to an hour or until a tooth pick inserted comes out clean.
Cool completely then cut into pieces before serving.
Pumpkin pie spice can be found pre made and is a mixture of nutmeg, cloves, ginger, and cinnamon.
You can freeze pumpkin cake! A pumpkin cake that has been pre-baked will actually hold it's moisture and flavor for up to 2 months in the freezer! After 2 months you may notice a change in the flavor of your cake as well as more of a dry texture.
Please keep in mind that nutritional information is a rough estimate and can vary greatly based on products used.