Preheat oven to 425 degrees. Line 12-cup muffin pan with cupcake liners. Set aside.
In a large bowl, whisk melted butter and sugar until combined. Add in eggs one at a time, mixing between each one. Add vanilla extract and lemon zest and mix together.
In a small bowl, add ½ cup of blueberries and smash with a fork. Add milk to the smashed blueberries. Set aside. In a medium bowl, whisk together flour, salt and baking powder. Add in 1¼ of the fresh blueberries and toss into the flour mixture. Reserve the remaining ¼ cup of blueberries to place on top of the muffins before baking.
Add ⅓ of the flour mixture to the butter mixture and stir to combine. Add half of the milk-blueberry mixture and stir to combine. Alternate with flour then milk again until you finish with the flour. Mix just until combined.
Fill each liner with batter until ¾ full. Top with blueberries and a sprinkle of turbinado sugar. Place in oven and immediately reduce temperature of oven to 375 degrees. Bake until golden brown on top, about 20 minutes. Remove from oven and let cool for 10 minutes before eating.