1. Preheat oven to 350 degrees Fahrenheit.
2. In a medium bowl, mix flour, sugar, salt, and baking powder. In a separate bowl, mix the wet ingredients. Add to flour and stir well; batter will be very thick! Gently fold in the blueberries.
3. In a separate bowl, mix ingredients for streusel mixture and set aside.
4. Fill muffin cups to the top with batter and cover with the topping mixture.
5. Bake for 15 minutes. Raise oven temperature to 400 degrees Fahrenheit and bake an additional 10 minutes until golden brown.
Bakery Secret: A Shiny Muffin Top
Sprinkle the top of your muffin with with granulated or coarse sugar for a shiny, crisp look.