Preheat the oven to 400 degrees.
Add the blueberries to a bowl and mix with one tablespoon of flour. Set that aside.
In a medium bowl, add the flour, salt, baking soda and baking powder. Mix to combine and set that aside.
In a large bowl, add the sugar and eggs. Add the sourdough starter, milk, butter, and vanilla. Mix well to combine.
Add the dry ingredients to the wet ingredients and mix until just combined. The batter will not be smooth, it’s ok if there are a few lumps left.
Add the blueberries to the batter and mix again until just combined. Do not overmix.
Line a muffin tin with muffin liners. Scoop equal amounts of batter into the muffin tins.
Bake for 20-22 minutes or until a toothpick is inserted and it comes out clean.
Allow the muffins to cool slightly and serve.