Preheat your oven to 350°F. Spray a 12-cup muffin pan with cooking spray.
In a medium bowl, stir together the flour, baking powder, and salt.
In a stand mixer with the paddle attachment, cream the butter and the sugar on medium speed until light and fluffy, about two minutes.
Reduce the speed to low, then slowly add in the eggs and vanilla. Increase the mixer speed to medium-high, and mix until well incorporated.
Return the mixer back to a low speed, and add in the flour mixture and sour cream. Mix until well incorporated. Fold in the blueberries.
Fill your muffin cups about three-quarters full, then sprinkle the streusel crumble on top of each muffin.
Bake about 24 - 28 minutes. If using a toothpick to test doneness, the toothpick should come out of the center of the muffin clean.
Store in an airtight container at room temperature.