Preheat 325 degrees F. Spray a 9"x9" pan with nonstick spray. Set aside.
In a medium bowl, whisk together the flour, baking powder, cinnamon, ground ginger, nutmeg, and salt. Set aside.
In the bowl of an electric mixer fitted with the paddle attachment, beat the sugar and eggs together on medium-high speed until light and fluffy, about 5 minutes. Add the oil and vanilla and beat on medium until combined, about 30 seconds. Add the pumpkin filling and mix until combined, about another 30 seconds.
Slowlhy and gently stir in the dry ingredients.
Pour the batter into your pan. Sprinkle on the streusel topping. Bake until a knife or toothpick inserted into the center comes out with a few moist crumbs on it, about 40 to 45 minutes.
Let the cake cool completely before adding the vanilla icing and serving.