Place muffin liners in a muffin tin and set aside. If your liners aren’t made of parchment and just paper, you might want to spray them with cooking spray.
In a bowl, toss the blueberries with the teaspoon of flour and set aside.
In medium bowl, whisk together the buttermilk, melted butter, sugar, neutral oil, eggs and vanilla extract. In a large bowl, whisk together the flour, salt, baking powder, baking soda. Pour the wet ingredients into the dry ingredients and mix until barely combined. Add the blueberries.
Cover the bowl with plastic wrap and allow to rest for at least 1 hour or you can allow them to rest in the fridge overnight. If you're resting them for an hour, no need to add them to the fridge.
Preheat the oven to 400 degrees F. Divide the batter amongst the twelve cavities in the muffin tin. Sprinkle the tops with turbinado sugar.
Transfer to the oven to bake for 7 minutes. Then immediately turn the oven’s temperature down to 350 degrees F and bake for an additional 10 to 12 minutes, until the tops are lightly golden brown and nicely domed.
Let the muffins cool in the pan for 10 minutes and then carefully remove and allow to cool on a cooling rack. Muffins will last up to 3 days when stored in an air-tight container.