Preheat oven to 350 degrees F. Line a 12-cup muffin tin with liners, set aside.

In a medium size bowl, whisk together flour, baking powder, salt and cinnamon. Gently stir in blueberries, making sure all the blueberries get coated well with the flour mixture. Set aside.

In a large mixing bowl, whisk egg and sugar together until combined (about 30 seconds). Add melted butter and whisk again until combined. Add lemon zest and vanilla and stir. Finally, add half the Greek yogurt and mix well and then the remaining yogurt and mix well.

Add the dry ingredients and gently mix just combined (batter will be very thick).

Divide batter equally among the 12 muffin cups.

Bake for 25-30 minutes or until a toothpick inserted comes out clean.

Remove from oven and let cool for 5 minutes in the pan and then move each muffin onto a cooling rack. Let sit for about 10 minutes.

While muffins are cooling, put melted butter in a small bowl. In another small bowl combine the cinnamon and sugar mix until combined.

Dip the tops of each muffin in the melted butter and then in the cinnamon-sugar mixture.

Enjoy!