Preheat the oven to 375 degrees F (190 degrees C). Line 18 muffin cups with paper liners and spray with cooking spray.
Prepare streusel topping: combine flour, white sugar, brown sugar, pumpkin pie spice, and salt in a small bowl. Add melted butter and mix together until crumbly; set aside.
Prepare muffins: combine flour, pumpkin pie spice, baking soda, salt, and baking powder in medium bowl. Whisk pumpkin, white sugar, brown sugar, oil, eggs, and vanilla together in a large bowl. Fold flour mixture into pumpkin mixture until just combined (some lumps may still remain).
Fill the prepared muffin cups 3/4 full. Top each with about 1 1/2 tablespoons reserved streusel mixture.
Bake in the center of the preheated oven until streusel is golden brown, muffins have risen, and a toothpick comes out with clean with just a few moist crumbs, 22 to 25 minutes. Let cool in the muffin tins for 5 minutes, then transfer to a wire rack to cool completely, about 15 minutes.
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