Preheat the oven to 425ºF.  Line a muffin tin with muffin liners. Set aside.

In a medium bowl, whisk together the all purpose flour, sugar, baking powder, salt and cinnamon. 

In another bowl or large measuring cup, whisk together the oil, melted butter, milk, eggs and vanilla extract until smooth. 

Make a well in the center of the flour mixture and pour in the milk/egg mixture.  Mix the batter until combined. 

Fold in the dried blueberries, until just combined.  Do not over mix. 

Use a large scoop to fill the muffin cups ¾  of the way full. Sprinkle the tops of the muffins with crumb topping if you’re using it. 

Bake for 5 minutes at 425ºF before reducing the heat to 375ºF.  Bake for 15-20 minutes more, until a toothpick comes out clean.  

Remove the pan from the oven and let the muffins cool in the pan for 5 minutes, before transferring the muffins to a wire rack.  

Serve warm or at room temperature.