Preheat oven to 350 degrees. Grease a 13 x 9 inch pan with butter. Coat with flour, dusting off the excess.
Start by creaming butter and both sugars in a stand mixer with the paddle attachment.
Next add in eggs, sour cream, and vanilla extract.
In a separate bowl combine flour, baking soda, and salt, set aside.
To the wet mixture, fold in the dry ingredients in two batches. Try not to over mix it will make the coffee cake tough.
Fold in blueberries and stir until combined. Pour cake into the greased pan.
For the crumb topping combine the flour, brown sugar, cinnamon and melted butter. Mixture will be similar to the consistency of wet sand.Crumble mixture on top of the cake.
Bake for 30-35 minutes until a tooth pick or knife can be inserted and comes out clean.