Preheat the oven to 350 degrees. Coat a muffin tray with coconut oil cooking spray.
Whisk the cooled melted butter with the sour cream, white sugar, egg, and lemon zest until well combined.
Mix the flour with the baking powder, baking soda, and salt until thoroughly combined.
Slowly add the flour mixture to the sour cream mixture until just combined.
Add most of the blueberries and gently fold them into the batter.
Fill 9 of the muffin cups evenly.
Push a few of the remaining blueberries into the top of each muffin.
Sprinkle 1 teaspoon of turbinado sugar to the top of each muffin. Side Note: I know that 1 tsp will seem like a lot, but trust me it makes the muffin top crisp and sugary delicious!
Place into the oven and bake for 24-26 minutes, or until a tester inserted into the center comes out clean.
Remove from the oven and let them rest for 10 minutes in the pan before removing them to a rack. Enjoy.