Creating this delicious Pumpkin Spice Coffee Cake is simple! Just follow these steps:

1. Preheat Your Oven: Set your oven to 350°F (175°C). Grease and flour a 9×13 inch baking pan.
2. Combine Dry Ingredients: In a large bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon, nutmeg, and ginger. Set aside.
3. Mix Sugars and Oil: In another bowl, combine the granulated sugar, brown sugar, and vegetable oil. Mix well.
4. Add Pumpkin and Eggs: Incorporate the pumpkin puree, eggs, and vanilla extract into the sugar mixture. Beat until smooth.
5. Combine Mixtures: Gradually add the dry ingredients into the wet mixture, stirring until just combined. Be careful not to overmix.
6. Prepare the Topping: In a bowl, mix together the chopped nuts, brown sugar, flour, cinnamon, and softened butter until crumbly.
7. Layer the Batter: Pour half of the batter into the prepared baking pan. Spread evenly.
8. Add Topping: Sprinkle half of the topping mixture over the batter in the pan, followed by the remaining batter. Finally, top with the remaining crumb topping.
9. Bake: Place the pan in the preheated oven and bake for 40-50 minutes, or until a toothpick inserted into the center comes out clean.
10. Cool the Cake: Once baked, remove from the oven and let it cool in the pan for 10-15 minutes. Then transfer to a wire rack to cool completely.

These straightforward steps will lead you to an incredible Pumpkin Spice Coffee Cake that is sure to impress!